Exposure apparatus and exposure method, and device manufacturing method

ABSTRACT

An exposure apparatus is equipped with a table which holds a wafer and is movable along an XY plane and has a grating provided on its rear surface, an encoder which irradiates a first measurement beam on the grating from below, receives a return light, and measures a first position information of the table when the table moves in a predetermined range, and another encoder which has a head section provided in a frame and irradiates a second measurement beam on a different grating on the table from the head section, receives a return light, and can measure a second position information of the table, concurrently with measurement of the first position information by the encoder when the table moves in predetermined range. A controller drives the table, based on position information having a higher reliability of the first and the second position information.

CROSS-REFERENCE TO RELATED APPLICATIONS

This non-provisional application claims the benefit of ProvisionalApplication No. 61/581,293 filed Dec. 29, 2011, and ProvisionalApplication No. 61/581,360 filed Dec. 29, 2011, the disclosures of whichare hereby incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to exposure apparatuses and exposuremethods, and device manufacturing methods, and more particularly to anexposure apparatus and an exposure method used in a lithography processto manufacture electron devices (microdevices), and a devicemanufacturing method using the exposure apparatus and the exposuremethod.

2. Description of the Background Art

Conventionally, in a lithography process to manufacture electron devices(microdevices) such as a semiconductor device (an integrated circuit andthe like), a liquid crystal display device and the like, a projectionexposure apparatus (a so-called stepper) employing a step-and-repeatmethod, or a projection exposure apparatus (so-called scanning stepper(also called a scanner)) employing a step-and-scan method is mainlyused.

In this type of exposure apparatus, in general, a position of a waferstage which moves two-dimensionally while holding a substrate such as awafer or a glass plate and the like on which a pattern is transferred(or formed) (hereinafter collectively called a wafer) was measured,using a laser interferometer. However, due to finer patternsaccompanying higher integration of semiconductor devices in recentyears, requirements for position control performance of a wafer stagewith higher accuracy have increased, and as a consequence, it has becomedifficult to ignore short-term variation of measurement values caused bytemperature change of the atmosphere on the beam path of a laserinterferometer, and/or air fluctuation which occurs due to the influenceof temperature gradient.

To improve such inconveniences, various proposals have been made ofinventions related to exposure apparatuses that employ an encoder havinga measurement resolution of the same level or higher than a laserinterferometer as a position measurement device of a wafer stage (forexample, refer to U.S. Patent Application Publication No. 2008/0088843).However, in the liquid immersion exposure apparatus disclosed in U.S.Patent Application Publication No. 2008/0088843 and the like, the waferstage (gratings provided on the upper surface of the wafer stage) may bedeformed influenced by heat of vaporization and the like due to theinfluence of the liquid evaporating, and there still was room forimprovement.

To improve such inconveniences, the inventor has previously proposed anexposure apparatus that is equipped with an encoder system whichirradiates a measurement beam on a grating provided on a rear surface ofa table holding a wafer from a head section provided on the tip of ameasurement arm consisting of a cantilever (for example, refer to, U.S.Patent Application Publication No. 2010/0073652, and U.S. PatentApplication Publication No. 2010/0073653).

However, according to further studies, in the encoder system using themeasurement arm described above, it became clear that the influence ofbackground vibration including floor vibration and the like was large ina band of around 100 Hz to 400 Hz. Especially, with the wafer sizeincreasing, the size of a wafer table on which the wafer is mounted alsowill increase, and for example, on a wafer table on which a wafer in thenear future having a diameter of 450 mm is mounted, the length of themeasurement arm used for position measurement will become 500 mm ormore, and it is expected that vibration of the arm tip from which themeasurement beam is to be emitted can no longer be ignored.

However, with more and more finer semiconductor devices, requirementsfor position control accuracy of the wafer has gradually become tighter,and now the maximum value of a permissible position error is about 1 nm.When such an accuracy is required, even in the encoder systems disclosedin U.S. Patent Application Publication No. 2010/0073652, U.S. PatentApplication Publication No. 2010/0073653 and the like described above, ameasurement error at a level that cannot be ignored may occur due totemporal drift of the grating pitch of the grating.

SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provideda first exposure apparatus which exposes an object by an energy beam viaan optical system, the apparatus comprising: a moving member holding theobject which is movable along a predetermined plane including a firstaxis and a second axis orthogonal to each other, and has a first gratingprovided at a position on an opposite side of the optical system withrespect to a surface on which the object is mounted; a first measurementsystem which measures a first position information of the moving-memberby irradiating a first measurement beam from below on the first gratingand receiving light from the first grating of the first measurementbeam, when the moving member moves in a first predetermined range withinthe predetermined plane; a second measurement system which has a headprovided in one of the moving member and outside of the moving member,and can measure a second position information of the moving memberconcurrently with measurement of the first position information by thefirst measurement system by irradiating a second measurement beam on asecond grating provided on the other of the moving member and outside ofthe moving member from the head and receiving light from the secondgrating of the second measurement beam, when the moving member moves inthe first predetermined range within the predetermined plane; and adriving system which drives the moving member within the firstpredetermined range, based on position information having a higherreliability of the first position information and the second positioninformation.

According to this apparatus, the moving member is driven within thefirst predetermined range by the driving system, based on positioninformation having a higher reliability of the first and the secondposition information measured by the first and the second measurementsystems, respectively. Accordingly, the moving member can be drivenconstantly with good precision within the first predetermined range,based on position information having high reliability.

According to a second aspect of the present invention, there is provideda device manufacturing method, comprising: exposing an object using thefirst exposure apparatus described above; and developing the objectwhich has been exposed.

According to a third aspect of the present invention, there is provideda second exposure apparatus which exposes a substrate via an opticalsystem, the apparatus comprising: a frame member which supports theoptical system; a substrate stage which has a mounting area of thesubstrate and a first grating member placed lower than the mountingarea; a driving system which drives the substrate stage; a firstmeasurement system which has a head section placed lower than the firstgrating member, and measures position information of the substrate stageby irradiating a first measurement beam from below to the first gratingmember, via the head section facing the first grating by the substratestage being positioned facing the optical system; a second measurementsystem which has a plurality of heads provided on one of the framemember and the substrate stage, and measures position information of thesubstrate stage by irradiating each of a second measurement beam via theplurality of heads on a second grating member provided on the other ofthe frame member and the substrate stage; and a controller whichcontrols a drive of the substrate stage by the driving system, based onposition information measured by at least one of one the secondmeasurement systems.

According to this apparatus, the drive of the substrate stage by thedriving system is controlled by the controller, based on positioninformation measured by at least one of the first measurement system andthe second measurement system. Accordingly, position information of thesubstrate stage is measured with high precision, and position control ofthe substrate stage with high precision becomes possible.

According to a fourth aspect of the present invention, there is provideda device manufacturing method, comprising: exposing an object using thesecond exposure apparatus described above; and developing the objectwhich has been exposed.

According to a fifth aspect of the present invention, there is provideda first exposure method in which an object is exposed by an energy beamvia an optical system, the method comprising: measuring positioninformation of a moving member on which the object is mounted and ismovable while holding the object along a predetermined plane including afirst axis and a second axis orthogonal to each other, in degrees offreedom of more than three including three degrees of freedom within thepredetermined plane when the moving member moves within a firstpredetermined range within an exposure station where the object isexposed by the energy beam, based on measurement information accordingto a first measurement system which includes a plurality of heads thateach measures position information of the moving member in at least onemeasurement direction, with the measurement direction being a firstdirection parallel to the first axis, a second direction parallel to thesecond axis, and a third direction orthogonal to the predeterminedplane, by each head irradiating each of a first measurement beam on agrating provided on a rear surface side of a mounting surface on whichthe object is mounted of the moving member and receiving each returnlight from the grating, and updating grid errors in a predeterminedmeasurement direction of a coordinate system of the first measurementsystem, based on a difference between position information of the movingmember in the predetermined measurement direction which is a part ofposition information used to drive the moving member in a firstpredetermined number of degrees of freedom of three or more includingthree degrees of freedom within the predetermined plane and redundantposition information of the moving member in the predeterminedmeasurement direction which is not used when driving the moving memberin the first predetermined number of degrees of freedom, while drivingthe moving member within the first predetermined range and controlling aposition of the moving member in directions of the first predeterminednumber of degrees of freedom based on the measurement information by theplurality of heads.

According to this method, based on measurement information by theplurality of heads, the moving member holding the object is driven inthe first predetermined range within the exposure station while theposition in a first predetermined number of degrees of freedom of threeor more including three degrees of freedom within the predeterminedplane is controlled, and an update of grid errors in the predeterminedmeasurement direction of the coordinate system of the first measurementsystem is performed. Accordingly, the object held by the moving memberis exposed by the energy beam via the optical system, while the positionin directions of three degrees of freedom at least within thepredetermined plane of the moving member is controlled on the coordinatesystem of the first measurement system on which an update of grid errorsin the predetermined measurement direction is performed. Accordingly,the object can be exposed with high precision.

According to a sixth aspect of the present invention, there is provideda device manufacturing method, comprising: exposing an object using thefirst exposure method described above; and developing the object whichhas been exposed.

According to a seventh aspect of the present invention, there isprovided a third exposure apparatus which exposes an object via anoptical system by an energy beam, the apparatus comprising: a movingmember holding the object which is movable along a predetermined planeincluding a first axis and a second axis that are orthogonal to eachother while having a grating at a position on an opposite side of theoptical system provided with respect to a mounting surface on which theobject is mounted; a first measurement system which has a plurality ofheads measuring position information of the moving member in at leastone measurement direction, with the measurement direction being a firstdirection parallel to the first axis, a second direction parallel to thesecond axis, and a third direction orthogonal to the predeterminedplane, by each of the plurality of heads irradiating each of a firstmeasurement beam on the grating and receiving return lights from thegrating, and measures position information of the moving member in themeasurement direction in degrees of freedom of more than three includingthree degrees of freedom within the predetermined plane based onmeasurement information according to the plurality of heads when themoving member moves within a first predetermined range within anexposure station where the object is exposed by the energy beam; and adriving system which drives the moving member while controlling aposition of the moving member in directions of a first predeterminednumber of degrees of freedom of three or more including three degrees offreedom within the predetermined plane based on measurement informationby the plurality of heads when the moving member moves in the firstpredetermined range, and updates grid errors in a predeterminedmeasurement direction of a coordinate system of the first measurementsystem, based on a difference between position information of the movingmember in the predetermined measurement direction which is a part ofposition information used to drive the moving member in the firstpredetermined number of degrees of freedom and redundant positioninformation of the moving member in the predetermined measurementdirection which is not used when driving the moving member in the firstpredetermined number of degrees of freedom.

According to this apparatus, by the driving system, the moving memberholding the object is driven in the first predetermined range within theexposure station while the position in a first predetermined number ofdegrees of freedom of three or more including three degrees of freedomwithin the predetermined plane is controlled, and an update of griderrors in the predetermined measurement direction of the coordinatesystem of the first measurement system is performed, based onmeasurement information by the plurality of heads. Accordingly, theobject held by the moving member is exposed by the energy beam via theoptical system, while the moving member is driven (position control isperformed) with high precision in directions of three degrees of freedomat least within the predetermined plane on the coordinate system of thefirst measurement system on which an update of grid errors in thepredetermined measurement direction is performed. Accordingly, theobject can be exposed with high precision.

According to an eighth aspect of the present invention, there isprovided a device manufacturing method, comprising: exposing an objectusing the third exposure apparatus described above; and developing theobject which has been exposed.

According to a ninth aspect of the present invention, there is provideda second exposure method in which a substrate is exposed via an opticalsystem, the method comprising: positioning a substrate stage having amounting area of the substrate and a first grating member placed lowerthan the mounting area so that the substrate stage faces the opticalsystem; measuring position information of the substrate stage by a firstmeasurement system which irradiates a first measurement beam from belowon the first grating member, via a head section facing the first gratingmember of the substrate stage positioned to face the optical system;measuring position information of the substrate stage by a secondmeasurement system which irradiates a second measurement beam, via eachof a plurality of heads provided in one of a frame member supporting theoptical system and the substrate stage, on a second grating memberprovided in the other of the frame member and the substrate stage; andcontrolling a drive of the substrate stage by a driving system, based onposition information measured by at least one of the first measurementsystem and the second measurement system.

According to a tenth aspect of the present invention, there is provideda device manufacturing method, comprising: exposing a substrate usingthe second exposure method described above; and developing the objectwhich has been exposed.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings;

FIG. 1 is a view schematically showing a structure of an exposureapparatus 100 related to a first embodiment;

FIG. 2A is a planar view showing a wafer stage WST in FIG. 1, and FIG.2B is a view (front view) of wafer stage WST when viewed from a −Ydirection;

FIG. 3A is a view (front view) of a measurement stage MST in FIG. 1 whenviewed from the −Y direction, FIG. 3B is a view (side view) ofmeasurement stage MST when viewed from a +X direction, and FIG. 3C is aplanar view showing measurement stage MST;

FIG. 4 is a view showing a placement of a first to a fourth top sideencoder systems, alignment systems, a multi-point AF system and the likethat the exposure apparatus in FIG. 1 is equipped with, with aprojection optical system serving as a reference;

FIG. 5 is a view used to describe a concrete placement of heads in thefirst to the fourth top side encoder systems in FIG. 4;

FIG. 6A is a schematic front view (when viewed from the −Y direction)showing a chuck unit, and FIG. 6B is a schematic planar view of thechuck unit;

FIG. 7 is a view used to describe a schematic structure of a first backside encoder system in FIG. 1;

FIG. 8A is a perspective view showing the tip of a measurement arm of asecond back side encoder system, and FIG. 8B is a planar view showingthe tip of the measurement arm in FIG. 8A;

FIG. 9A is a view used to describe a schematic structure of the firstback side encoder system in FIG. 1, and FIG. 9B is a perspective viewshowing the tip of a measurement arm of a second back side encodersystem;

FIGS. 10A and 10B are views used to describe position measurement of afine movement stage WFS in directions of six degrees of freedomperformed using the first back side encoder system 70A, and differencemeasurement of the XYZ grids;

FIGS. 11A to 11C are views used to describe a situation where an ΔX mapis obtained by difference measurement;

FIGS. 12A and 12B are views showing examples of a ΔY map and a ΔZ map,respectively;

FIG. 13A is a view showing a situation of a position measurementprocessing of a wafer table WTB, concurrently, by the first top sideencoder system and the first back side encoder system, and FIG. 13B is aview showing an example of a hybrid position signal which can beobtained by the position measurement described above when a switchingsection is set to a first mode;

FIGS. 14A and 14B are views to describe refreshing of a coordinatesystem of the first top side encoder system;

FIG. 15 is a view used to explain a structure of an unloading device;

FIG. 16 is a block diagram showing an input/output relation of a maincontroller mainly structuring a control system of the exposure apparatusrelated to the first embodiment;

FIG. 17 is a view showing an example of a concrete structure of a firstand a second fine movement stage position measurement systems in FIG.16;

FIG. 18 is a block diagram showing an example of a structure of aswitching section 150A in FIG. 16;

FIG. 19 is a view (No. 1) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIGS. 20A to 20D are views (No. 2) used to describe a concurrentprocessing operation using wafer stage WST and measurement stage MST,and also are views to describe a loading procedure onto a wafer stage;

FIG. 21 is a view (No. 3) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 22 is a view (No. 4) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 23 is a view (No. 5) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 24 is a view (No. 6) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 25 is a view (No. 7) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIGS. 26A to 26D are views (No. 8) used to describe a concurrentprocessing operation using wafer stage WST and measurement stage MST,and also are views used to describe carrying in a next wafer to an areabelow a chuck unit;

FIG. 27 is a view (No. 9) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 28 is a view (No. 10) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST, and also is aview to describe traverse checking;

FIG. 29 is a view (No. 11) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 30 is a view (No. 12) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 31 is a view (No. 13) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIGS. 32A to 32D are views (No. 14) used to describe a concurrentprocessing operation using wafer stage WST and measurement stage MST,and also are views used to describe a procedure of carrying a waferwaiting at a standby position to a delivery position between a carriersystem;

FIG. 33 is a view (No. 15) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 34 is a view (No. 16) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIG. 35 is a view (No. 17) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIGS. 36A to 36D are views (No. 18) used to describe a concurrentprocessing operation using wafer stage WST and measurement stage MST,and also are views used to describe an unloading procedure of a waferwhich has been exposed from a wafer stage:

FIG. 37 is a view (No. 19) used to describe a concurrent processingoperation using wafer stage WST and measurement stage MST;

FIGS. 38A to 38E are views (No. 20) used to describe a concurrentprocessing operation using wafer stage WST and measurement stage MST,and also are views used to describe a procedure of carrying a waferwaiting at a standby position 2 to a delivery position between a carriersystem;

FIG. 39 is a schematic planar view showing a structure of an exposureapparatus related to a second embodiment;

FIG. 40 is a block diagram showing an input/output relation of a maincontroller mainly structuring a control system of the exposure apparatusrelated to the second embodiment;

FIG. 41 is a view used to describe a concrete placement of heads in thefirst and second top side encoder systems in FIG. 39;

FIG. 42 is a view (No. 1) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 43 is a view (No. 2) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 44 is a view (No. 3) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 45 is a view (No. 4) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 46 is a view (No. 5) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 47 is a view (No. 6) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 48 is a view (No. 7) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 49 is a view (No. 8) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 50 is a view (No. 9) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 51 is a view (No. 10) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 52 is a view (No. 11) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 53 is a view (No. 12) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 54 is a view (No. 13) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment;

FIG. 55 is a view (No. 14) used to describe a concurrent processingoperation using two wafer stages and a measurement stage in the exposureapparatus related to the second embodiment; and

FIG. 56 is a view used to describe a modified example when a measurementsystem measuring a position of a measurement table consisting of anencoder system is used, instead of a measurement stage positionmeasurement system consisting of an interferometer system.

DESCRIPTION OF THE EMBODIMENTS First Embodiment

Hereinafter, a first embodiment will be described, referring to FIGS. 1to 38E.

FIG. 1 schematically shows a structure of an exposure apparatus 100related to the first embodiment. This exposure apparatus 100 is aprojection exposure apparatus using a step-and-scan method, or aso-called scanner. As it will be described later on, in the presentembodiment, a projection optical system PL is provided, and hereinafter,the description will be made with a direction parallel to an opticalaxis AX of this projection optical system PL referred to as a Z-axisdirection (Z direction), a direction in which a reticle and a wafer arerelatively scanned within a plane orthogonal to the Z-direction referredto as a Y-axis direction (Y direction), and a direction orthogonal tothe Z-axis and the Y-axis referred to as an X-axis direction (Xdirection), and rotation (tilt) directions around the X-axis, theY-axis, and the Z-axis referred to as θx, θy, and θz directions,respectively.

Exposure apparatus 100, as shown in FIG. 1, is equipped with an exposuresection 200 placed near the edge on the +Y side on a base board 12, ameasurement section 300 placed near the edge on the −Y side on baseboard 12, a wafer stage WST and a measurement stage MST which movetwo-dimensionally within an XY-plane independently on base board 12, acontrol system for these sections, and the like. In the descriptionbelow, for the sake of convenience, as the terms for showing the placesof exposure section 200 and measurement section 300, respectively, willbe referred to as exposure station 200 and measurement station 300,using the same reference signs as the exposure section and themeasurement section.

Here, base board 12 is supported in a substantially horizontal manner(parallel to the XY-plane) on a floor surface by a vibration-proofmechanism (omitted in drawings). Base board 12 consists of a memberhaving a flat outer shape. Incidentally, in FIG. 1, wafer stage WST ispositioned at exposure station 200, and a wafer W is held on wafer stageWST (to be more specific, on a wafer table WTB to be described lateron). Further, measurement stage MST is positioned within or nearexposure station 200. During the exposure operation of wafer W usingwafer stage WST, measurement stage MST is positioned at a predeterminedposition (withdrawal position or waiting position) away from the areabelow projection optical system PL so as not to come in contact withwafer stage WST moving below projection optical system PL. Further,prior to the exposure operation of wafer W being completed, measurementstage MST is relatively moved to approach wafer stage WST moving belowprojection optical system PL, and at the point when the exposure hasbeen completed at the latest, wafer stage WST and measurement stage MSTare positioned to be in proximity (or in contact). Furthermore, waferstage WST and measurement stage MST in proximity to each other are movedwith respect to projection optical system PL, and measurement stage MSTis placed to face projection optical system PL instead of wafer stageWST. Incidentally, at least a part of the relative movement to positionwafer stage WST and measurement stage MST in proximity can be performed,after the exposure operation of wafer W.

Exposure section 200 is equipped with an illumination system 10, areticle stage RST, a projection unit PU, a local liquid immersion device8 and the like.

Illumination system 10, as disclosed in, for example, U.S. PatentApplication Publication No. 2003/0025890 and the like, includes a lightsource; and an illumination optical system which has an illuminanceequalizing optical system including an optical integrator and the like,and a reticle blind and the like (none of which are shown). Illuminationsystem 10 illuminates a slit-shaped illumination area IAR on a reticle Rset (limited) by a reticle blind (also called a masking system) withillumination light (exposure light) IL at a substantially equalilluminance. Here, as illumination light IL, as an example, an ArFexcimer laser beam (wavelength 193 nm) is used.

On reticle stage RST, reticle R that has a circuit pattern and the likeformed on its pattern surface (the lower surface in FIG. 1) is fixed,for example, by vacuum chucking. Reticle stage RST is finely drivablewithin the XY-plane and is also drivable in a scanning direction (theY-axis direction, which is the lateral direction of the page surface inFIG. 1) at a predetermined scanning velocity, by a reticle stage drivingsystem 11 (not shown in FIG. 1, refer to FIG. 16) including, forexample, a linear motor and the like.

Position information within the XY-plane (including rotationalinformation in the θz direction) of reticle stage RST is constantlydetected, using a reticle laser interferometer (hereinafter referred toas a “reticle interferometer”) 13 via a movable mirror 15 (a Y movablemirror (or a retroreflector) having a reflection surface orthogonal tothe Y-axis direction and an X movable mirror having a reflection surfaceorthogonal to the X-axis direction are actually provided) fixed toreticle stage RST, at a resolution of, for example, around 0.25 nm. Themeasurement values of reticle interferometer 13 are sent to a maincontroller 20 (not shown in FIG. 1, refer to FIG. 16). Incidentally,position information of reticle stage RST can be measured using anencoder system disclosed in, for example, U.S. Pat. No. 7,839,485 andthe like, instead of reticle interferometer 13. In this case, one of agrating member (scale plate or a grid plate) on which a grating isformed and an encoder head can be provided on the lower surface side ofreticle stage RST, and the other can be placed below reticle stage RST,or one of the grating section and the encoder head can be provided onthe upper surface side of reticle stage RST, and the other can be placedabove reticle stage RST. Further, reticle stage RST can have acoarse/fine movement structure as in wafer stage WST to be describedlater on.

Projection unit PU is placed below reticle stage RST in FIG. 1.Projection unit PU is supported by a main frame (metrology frame) BD,which is supported horizontally by a support member not shown, via aflange section FLG provided on the outer circumference portion of theprojection unit. Main frame BD structures a part of a main section frameof exposure apparatus 100 on which at least a part of an illuminationoptical system or reticle stage RST is installed, and in the presentembodiment, is supported by a plurality of (for example, three or four)support members (not shown) placed on an installing surface (forexample, a floor surface and the like) via each of the vibrationisolation mechanisms. Incidentally, on the installing surface, baseboard 12 which will be described later on and the like are placed.Further, the vibration isolation mechanism can be placed in between eachsupport member and main frame BD. Furthermore, as disclosed in, forexample, PCT International Publication No. 2006/038952, projection unitPU can be supported in a suspended manner with respect to a part of themain section frame placed above projection unit PU.

Projection unit PU includes a barrel 40, and projection optical systemPL held within barrel 40. As projection optical system PL, for example,a dioptric system is used consisting of a plurality of optical elements(lens elements) disposed along optical axis AX parallel to the Z-axis.Projection optical system PL, for example, is telecentric on both sides,and has a predetermined projection magnification (e.g., ¼, ⅕, or ⅛ andthe like). Therefore, when illumination area IAR on reticle R isilluminated by illumination light IL from illumination system 10, byillumination light IL which passes through reticle R placed so that afirst plane (object plane) of projection optical system PL and thepattern surface are substantially coincident, a reduced image of acircuit pattern (a reduced image of part of a circuit pattern) withinillumination area IAR of reticle R is formed via projection opticalsystem PL (projection unit PU), in an area (hereinafter also referred toas an exposure area) IA, conjugate to illumination area IAR, on wafer Wwhich is placed on a second plane (image plane) side of projectionoptical system PL and whose surface is coated with a resist (sensitiveagent). And, by simultaneously driving reticle stage RST and wafer stageWST (to be more accurate, fine movement stage WFS to be described laterholding wafer W), reticle R is relatively moved in the scanningdirection (Y-axis direction) with respect to illumination area IAR(illumination light IL), while wafer W is relatively moved in thescanning direction (Y-axis direction) with respect to exposure area IA(illumination light IL), and scanning exposure of a shot area (dividedarea) on wafer W is performed, transferring the pattern of reticle R onthe shot area. That is, in the present embodiment, the pattern ofreticle R is generated on wafer W using illumination system 10 andprojection optical system PL, and the pattern is formed on wafer W byexposing a sensitive layer (resist layer) on wafer W with illuminationlight IL.

Local liquid immersion device 8 is provided, corresponding to exposureapparatus 100 which performs exposure based on a liquid immersionmethod. Local liquid immersion device 8 includes a liquid supply device5, a liquid recovery device 6 (none of which are shown in FIG. 1, referto FIG. 16), and a nozzle unit 32 or the like. Nozzle unit 32, as shownin FIG. 1, is supported in a suspended manner by main frame BDsupporting projection unit PU or the like via a support member notshown, and surrounds the periphery of the lower end section of barrel 40holding an optical element which structures projection optical system PLclosest to the image plane side (wafer W side), in this case, lens(hereinafter also referred to as a “tip lens” or a “final lens”) 191.Nozzle unit 32 is equipped with a supply port and a recovery port of aliquid Lq, a lower surface where wafer W faces and in which a recoveryport is provided, liquid supply pipe 31A and liquid recovery pipe 31B(none of which are shown in FIG. 1, refer to FIG. 4) and a supplypassage and a recovery passage connected to the pipes, respectively.Liquid supply pipe 31A is connected to one end of a supply pipe which isnot shown whose other end is connected to liquid supply device 5 (notshown in FIG. 1, refer to FIG. 16), and liquid recovery pipe 31B isconnected to one end of a recovery pipe which is not shown whose otherend is connected to liquid recovery device 6 (not shown in FIG. 1, referto FIG. 16). Further, nozzle unit 32 has a supply passage and a recoverypassage within, and liquid supply pipe 31A and liquid recovery pipe 31Bare connected to a supply port and a recovery port, respectively, viathe supply passage and the recovery passage. Furthermore, nozzle unit 32has an opening section through which illumination light IL emitted fromprojection optical system PL passes on its lower surface, and therecovery port, is placed in the periphery of the opening section. In thepresent embodiment, while the supply port is provided on the inner sidesurface of nozzle unit 32 surrounding the tip lens, another supply portdifferent from the supply port can be provided on the lower surface sideon the inner side of the recovery port with respect to the openingsection of nozzle unit 32.

In the present embodiment, main controller 20 controls liquid supplydevice 5 (refer to FIG. 16) and supplies liquid to a space between tiplens 191 and wafer W via liquid supply pipe 31A and nozzle unit 32, andalso controls liquid recovery device 6 (refer to FIG. 16) and recoversliquid from between tip lens 191 and wafer W via nozzle unit 32 andliquid recovery pipe 31B. On this operation, main controller 20 controlsliquid supply device 5 and liquid recovery device 6 so that the amountof the liquid supplied and the amount of the liquid recovered areconstantly equal. Accordingly, a fixed quantity of liquid Lq (refer toFIG. 1) is constantly replaced and held between tip lens 191 and waferW. Local liquid immersion device 8 forms a liquid immersion area belowprojection optical system PL by liquid Lq supplied via nozzle unit 32,as well as recovers the liquid from the liquid immersion area via nozzleunit 32 and holds liquid Lq only at a part of wafer W, or in otherwords, can form a liquid immersion area by confining liquid Lq on theupper surface of wafer stage WST (fine movement stage WFS) placed facingthe projection optical system PL, or consequently, by confining theliquid within a local area smaller than the surface of wafer W.Therefore, nozzle unit 32 can also be referred to as a liquid immersionmember, a liquid immersion space forming member, a Liquid Confinementmember, a Liquid Containment member and the like. In the presentembodiment, as the liquid above, pure water which transmits the ArFexcimer laser beam (light having a wavelength of 193 nm) is used.Incidentally, refractive index n of the pure water to the ArF excimerlaser beam is about 1.44, and in the pure water, the wavelength ofillumination light IL is shortened to 193 nm×1/n=around 134 nm.

In the present embodiment, while nozzle unit 32 is supported in asuspended manner by main frame BD, nozzle unit 32 can be provided in aframe member different from main frame BD such as, for example, a framemember placed on the installing surface previously described differentfrom main frame BD. This can suppress or prevent the vibrationtravelling from nozzle unit 32 to projection optical system PL. Further,a part of nozzle unit 32, on the lower surface side of nozzle unit 32 incontact with liquid Lq (an interface of the liquid immersion area), canbe movable, and a part of nozzle unit 32 can be moved so that a relativevelocity between wafer stage WST and nozzle unit 32 becomes small at thetime of movement of wafer stage WST. This can suppress or prevent a partof liquid Lq separating from the liquid immersion area and the liquidremaining on the upper surface of wafer stage WST or on the surface ofwafer W, especially during the exposure operation of wafer W. In thiscase, during the movement of wafer stage WST, a part of nozzle unit 32can be constantly moved, or a part of nozzle unit 32 can be moved in apart of the exposure operation, such as, for example, only in thestepping operation of wafer stage WST. Further, a part of nozzle unit 32can be, for example, a movable unit having the recovery port and atleast a part of the lower surface, or a plate relatively movable withrespect to nozzle unit 32, having a lower surface in contact with theliquid.

Besides such sections; exposure section 200 is equipped with a firstfine movement stage position measurement system 110A including a firstback side encoder system 70A having a measurement arm 71A which issupported substantially in a cantilevered state (supported near an edge)via a support member 72A from main frame BD, and a first top sideencoder system 80A (not shown in FIG. 1, refer to FIG. 16 and the like)to be described later on. However, the first fine movement stageposition measurement system 110A will be described after the descriptionof the fine movement stage which will be described later on, for thesake of convenience.

Measurement section 300 is equipped with an alignment device 99 providedin main frame BD, a multi-point focal point detection system(hereinafter, shortly referred to as a multi-point AF system) (90 a, 90b) (not shown in FIG. 1, refer to FIG. 16 and the like) provided in mainframe ED, and a second fine movement stage position measurement system110B that includes a second back side encoder system 70B having ameasurement arm 71B which is supported substantially in a cantileveredstate (supported near an edge) via a support member 72B from main frameBD, and a second top side encoder system (not shown in FIG. 1, refer toFIG. 16 and the like) to be described later on. Further, in the vicinityof alignment device 99, as shown in FIG. 1, a chuck unit 120 isprovided. Incidentally, the second fine movement stage positionmeasurement system 110B will also be described after the description ofthe fine movement stage which will be described later on, for the sakeof convenience. Further, alignment device 99 is also referred to as analignment detection system or a mark detection system.

Alignment device 99 includes five alignment systems AL1, and AL2 ₁ toAL2 ₄ which are shown in FIG. 4. To describe this in detail, as shown inFIGS. 4 and 5, a primary alignment system AL1 is placed on a straightline (hereinafter referred to as a reference axis) LV which passesthrough the center of projection unit PU (optical axis AX of projectionoptical system PL, also coinciding with the center of exposure area IApreviously described in the present embodiment) and is also parallel tothe Y-axis, in a state where the detection center is located at aposition a predetermined distance away to the −Y side from optical axisAX. On one side and the other side in the X-axis direction with primaryalignment system AL1 in between, secondary alignment systems AL2 ₁ andAL2 ₂, and AL2 ₃ and AL2 ₄ are provided, respectively, with thedetection centers placed substantially symmetric to reference axis LV.That is, the detection centers of the five alignment systems AL1, andAL2 ₁ to AL2 ₄ are placed along the X-axis direction. As each of thefive alignment systems AL1, and AL2 ₁ to AL2 ₄, for example, an FIA(Field Image Alignment) system is used that employs an image processingmethod of irradiating a broadband detection beam which does not exposethe resist on the wafer onto an object mark so that an image of theobject mark formed on a light receiving surface by the reflection lightfrom the object mark and an image of an index (an index pattern on anindex plate provided within each alignment system) not shown are imagedusing an imaging device (such as a CCD), and imaging signals are output.Imaging signals from the five alignment systems AL1, and AL2 ₁ to AL2 ₄are supplied to main controller 20 (refer to FIG. 16). Incidentally, thedetailed structure of alignment device 99 is disclosed in, for example,U.S. Patent Application Publication No. 2009/0233234. Further, alignmentsystems AL1 and AL2 ₁ to AL2 ₄ are each not limited to the imagingmethod, and for example, can employ a method of irradiating a coherentmeasurement light on an alignment mark (diffraction grating), anddetecting a diffracted light generated from the mark.

As the multi-point AF system shown in FIGS. 4 and 5, a multi-point AFsystem which employs an oblique-incidence method is provided, consistingof a light transmitting system 90 a and a light receiving system 90 b. Astructure similar to the multi-point AF system (90 a, 90 b) is disclosedin, for example, U.S. Pat. No. 5,448,332 and the like. In the presentembodiment, as an example, light transmitting system 90 a and lightreceiving system 90 b are placed symmetric to reference axis LV atpositions the same distance apart on the +Y side of a straight line(reference axis) LA, which passes through the detection center ofprimary alignment system AL1 and is parallel to the X-axis. The intervalin the X-axis direction between light transmitting system 90 a and lightreceiving system 90 b is set wider than the interval between a pair ofscales 39 ₁ and 39 ₂ (refer to FIG. 2A) provided on wafer table WTB tobe described later on.

A plurality of detection points of the multi-point AF system (90 a, 90b) is placed at a predetermined interval along the X-axis direction onthe surface subject to detection. In the present embodiment, forexample, the detection points are placed in a shape of a matrix of onerow M columns (M is the total number of detection points) or two rows Ncolumns (N is ½ of the total number of detection points). In FIGS. 4 and5, the plurality of detection points on which the detection beams areirradiated is not shown individually, and is shown as a detection areaAF extending elongated in the X-axis direction between lighttransmitting system 90 a and light receiving system 90 b. Because thelength in the X-axis direction of this detection area AF is set toaround the same as the diameter of wafer W, position information(surface position information) of the substantially entire surface ofwafer W in the Z-axis direction can be measured by simply scanning waferW once in the Y-axis direction. Further, regarding the Y-axis direction,because this detection area AF is placed between projection opticalsystem PL (exposure area IA) and the detection area of the alignmentsystems (AL1, AL2 ₁, AL2 ₂, AL2 ₃, and AL2 ₄), it is possible for themulti-point AF system and the alignment systems to concurrently performthe detection operations.

Incidentally, while the plurality of detection points is arranged in aone row M columns or two rows N columns manner, the number of rowsand/or columns are/is not limited to this. However, in the case thenumber of rows is two or more, it is preferable to arrange the positionof the detection points in the X-axis direction differently in differentrows. Furthermore, while the plurality of detection points is placedalong in the X-axis direction, besides such an arrangement, all or apart of the plurality of detection points can be placed at differentpositions regarding the Y-axis direction. For example, the plurality ofdetection points can be placed along a direction intersecting both theX-axis and the Y-axis. That is, only the position in at least the X-axisdirection has to be different for the plurality of detection points.Further, in the present embodiment, while the detection beam isirradiated on the plurality of detection points, for example, thedetection beam can be irradiated entirely on detection area AF.Furthermore, the length in the X-axis direction of detection area AFdoes not have to be around the same as the diameter of wafer W.

As it can be seen from FIGS. 1, 2B and the like, wafer stage WST has acoarse movement stage WCS, and a fine movement stage WFS which issupported in a non-contact state by coarse movement stage WCS via anactuator (for example, including at least one of a voice coil motor andan EI core) and can relatively move with respect to coarse movementstage WCS. To coarse movement stage WCS, although it is not shown, atube carrier placed on a guide surface provided separately on the +Xside (or the −X side) of base board 12 is connected, via a tube to whichpiping and wiring is integrated. The tube carrier supplies power usagesuch as electric power (electric current), cooling medium, compressedair, vacuum and the like to coarse movement stage WCS via the tube.Further, a part of the power usage supplied to coarse movement stage WCS(for example, vacuum and the like) is supplied to fine movement stageWFS. The tube carrier is driven in the Y-axis direction following waferstage WST by main controller 20, for example, via a linear motor and thelike. The drive of the tube carrier in the Y-axis direction does notnecessarily have to strictly follow wafer stage WST in the Y-axisdirection, as long as the tube carrier follows wafer stage WST within apermissible range. Further, the tube carrier can be placed on base board12, and in this case, the tube carrier can be driven by a planar motorto be described later which drives coarse movement stage WCS.Incidentally, the tube carrier can also be called a cable carrier, or afollower. Further, wafer stage WST does not necessarily have to have acoarse/fine movement structure.

Wafer stage WST (coarse movement stage WCS) is driven with predeterminedstrokes in the X-axis and Y-axis directions, and also finely driven inthe θz direction by a coarse movement stage driving system 51A includingthe planar motor to be described later on (refer to FIG. 16). Further,fine movement stage WFS is driven in directions of six degrees offreedom (in each of the X-axis, the Y-axis, the Z-axis, the θx, the θy,and the θz directions) by a fine movement stage driving system 52Aincluding the actuator previously described (refer to FIG. 16) withrespect to coarse movement stage WCS. Incidentally, coarse movementstage WCS can be driven in directions of six degrees of freedom by theplanar motor to be described later on.

Position information at least within the XY-plane (including rotationalinformation in the θz direction) of wafer stage WST (coarse movementstage WCS) is measured by a wafer stage position measurement system 16A(refer to FIGS. 1 and 16) consisting of an interferometer system.Further, position information in directions of six degrees of freedom offine movement stage WFS supported by coarse movement stage WCS inexposure station 200 is measured by the first fine movement stageposition measurement system 110A (refer to FIG. 1). Incidentally, waferstage position measurement system 16A does not necessarily have to beprovided. In this case, position information in directions of sixdegrees of freedom of wafer stage WST in exposure station 200 can bemeasured with only the first fine movement stage position measurementsystem 110A.

Further, when coarse movement stage WCS is at measurement station 300,position information in directions of six degrees of freedom of finemovement stage WFS supported by coarse movement stage WCS is measured bya second fine movement stage position measurement system 110B (refer toFIG. 1).

Further, within measurement station 300, when performing focus mappingand the like to be described later on, position information of finemovement stage WFS is measured also by a third back side encoder system70C and a third top side encoder system 80C (refer to FIG. 16) to bedescribed later on. In the embodiment, because the positions in the Ydirection differ with the detection center of alignment device 99 andthe detection point of the multi-point AF system as is previouslydescribed, the third back side encoder system 70C and the third top sideencoder system 80C are provided separately from the second fine movementstage position measurement system 110B. Therefore, in mark detection ofwafer W and the like by alignment device 99, the second fine movementstage position measurement system 110B can measure position informationof wafer stage WST at substantially the same position as the detectioncenter of alignment device 99 at least for the Y direction, and inmeasurement of position information in the Z direction of wafer W andthe like by multi-point AF system, the third back side encoder system70C and the third top side encoder system 80C can measure positioninformation of wafer stage WST at substantially the same position as thedetection point of the multi-point AF system at least for the Ydirection.

Incidentally, in the case the positions in the Y direction aresubstantially the same, or the spacing in the Y direction is small withthe detection center of alignment device 99 and the detection point ofthe multi-point AF system, the third back side encoder system 70C andthe third top side encoder system 80C do not necessarily have to beprovided. In this case, also in the measurement operation of themulti-point AF system, the second fine movement stage positionmeasurement system 110B can be used to measure the position informationof wafer stage WST. Further, even if the positions are different withthe detection center of alignment device 99 and the detection point ofthe multi-point AF system, in the case that the third back side encodersystem 70C and the third top side encoder system 80C are not providedand only the second fine movement stage position measurement system 110Bis used, the second fine movement stage position measurement system 110Bcan be placed so that position information of wafer stage WST ismeasured in between the detection center of alignment device 99 and thedetection point of the multi-point AF system in the Y direction, suchas, for example, in the center.

Furthermore, position information of fine movement stage WFS betweenexposure station 200 and measurement station 300, that is, between themeasurement ranges of the first fine movement stage position measurementsystem 110A and the second fine movement stage position measurementsystem 110B, is measured by a fourth top side encoder system 80D (referto FIG. 16) to be described later on. Incidentally, in the range whereposition information of wafer stage can no longer be measured by thefirst and the second fine movement stage position measurement systems110A and 110B, or in other words, outside the measurement rangepreviously described, the measurement device for measuring the positioninformation of wafer stage WST is not limited to the fourth top sideencoder system 80D, and other measurement devices, such as for example,the interferometer system, an encoder system having a detection methodand/or structure different from the fourth top side encoder system 80D,or the like can also be used.

Further, position information of measurement stage MST within theXY-plane is measured by a measurement stage position measuring system16B (refer to FIGS. 1 and 16), consisting of an interferometer system.Incidentally, the measurement device for measuring the positioninformation of measurement stage MST is not limited to theinterferometer system, and other measurement devices such as forexample, an encoder system (including the fifth top side encoder systemwhich will be described later on) can also be used.

Measurement values (position information) of wafer stage positionmeasurement system 16A, measurement stage position measuring system 16B,and the fourth top side encoder system 80D are supplied to maincontroller 20 (refer to FIG. 16), for position control of coarsemovement stage WCS, measurement stage MST, and fine movement stage WFS,respectively. Further, measurement results of the first and the secondfine movement stage position measurement systems 110A and 110B, and thethird back side encoder system 70C and the third top side encoder system80C are supplied to main controller 20 (refer to FIG. 16) via switchingsections 150A to 150C, respectively, that will be described later on,for position control of coarse movement stage WCS, measurement stageMST, and fine movement stage WFS, respectively.

Now, details of the structure and the like of the stage systems,including the various measurement systems described above will bedescribed. First of all, wafer stage WST will be described.

Coarse movement stage WCS, as shown in FIG. 28, is equipped with acoarse movement slider section 91, a pair of side wall sections 92 a and92 b, and a pair of stator sections 93 a and 93 b. Coarse movementslider section 91 consists of a rectangular plate shaped member whoselength in the X-axis direction in a planar view (when viewing from the+Z direction) is slightly longer than the length in the Y-axisdirection. The pair of side wall sections 92 a and 92 b each consist ofa rectangular plate shaped member whose longitudinal direction is in theY-axis direction, and are each fixed to the upper surfaces on one endand the other end, respectively, in the longitudinal direction of coarsemovement slider section 91 in a state parallel to a YZ-plane. The pairof stator sections 93 a and 93 b is fixed, facing toward the center inthe center along the Y-axis direction on each of the upper surfaces ofside wall sections 92 a and 92 b. Coarse movement stage WCS, as a whole,has a short rectangular parallelepiped shape with openings in the centerof the X-axis direction on the upper surface and in both side surfacesin the Y-axis direction. That is, in coarse movement stage WCS, a spaceis formed inside penetrated in the Y-axis direction. Measurement arms71A and 71B are inserted into this space, at the time of exposure, thetime of alignment and the like which will be described later on.Incidentally, the length in the Y-axis direction of side wall sections92 a and 92 b can be substantially the same as the stator sections 93 aand 93 b. That is, side wall sections 92 a and 92 b can be provided onlyin the center along the Y-axis direction on the upper surface of one endand the other end in the longitudinal direction of coarse movementslider section 91. Further, coarse movement stage WCS only has to bemovable supporting fine movement stage WFS, and can also be referred toas a main section, a moving body, or a movable body of wafer stage WST.

Inside base board 12, as shown in FIG. 1, a coil unit is housed thatincludes a plurality of coils 17 which are placed in the shape of amatrix with the XY two-dimensional directions serving as a row directionand a column direction. Incidentally, base board 12 is placed belowprojection optical system PL so that its surface is substantiallyparallel with the XY plane.

Corresponding to the coil units, on the bottom surface of coarsemovement stage WCS, or in other words, on the bottom surface of coarsemovement slider section 91, as shown in FIG. 2B, a magnet unit isprovided, consisting of a plurality of permanent magnets 18 placed inthe shape of a matrix with the XY two-dimensional directions serving asa row direction and a column direction. The magnet unit, along with thecoil unit of base board 12, structures coarse movement stage drivingsystem 51A (refer to FIG. 16) consisting of an electromagnetically(Lorentz force) driven planar motor like the ones disclosed in, forexample, U.S. Pat. No. 5,196,745 and the like. The magnitude and thedirection of current supplied to each coil 17 structuring the coil unitare controlled by main controller 20.

On the bottom surface of coarse movement slider section 91 in thevicinity of the magnet unit described above, a plurality of air bearings94 is fixed. Coarse movement stage WCS is supported by levitation abovebase board 12 by the plurality of air bearings 94 via a predeterminedclearance gap (clearance, gap), for example, a clearance gap of aroundseveral μm, and is driven by coarse movement stage driving system 51A inthe X-axis direction, the Y-axis direction, and the θz direction.

Incidentally, coarse movement stage driving system 51A is not limited tothe electromagnetically (Lorentz force) driven planar motor, and forexample, a planar motor which employs a variable reluctance drive methodcan also be used. Besides this, coarse movement stage driving system 51Acan be structured using a magnetically levitated type planar motor, andwith the planar motor, coarse movement stage WCS can be driven indirections of six degrees of freedom. In this case, air bearings do nothave to be provided on the bottom surface of coarse movement slidersection 91.

The pair of stator sections 93 a and 93 b are each made of a memberwhose external shape is a plate, and coil units CUa and CUb consistingof a plurality of coils used to drive fine movement stage WFS are housedinside. The magnitude and the direction of current supplied to each coilstructuring coil units CUa and CUb are controlled by main controller 20.

Fine movement stage WFS, as shown in FIG. 28, is equipped with a mainsection 81, a pair of mover sections 82 a and 82 b fixed to one edge andthe other edge in the longitudinal direction of main section 81,respectively, and wafer table WTB consisting of a plate member having arectangular shape in a planar view integrally fixed to the upper surfaceof main section 81.

Main section 81 consists of an octagonal plate shaped member whoselongitudinal direction is in the X-axis direction in a planar view. Onthe lower surface of main section 81, a scale plate 83 consisting of aplate shaped member of a predetermined thickness and a predeterminedshape, such as for example, a rectangular shape or an octagonal shapeslightly larger than main section 81 in a planar view, is placed andfixed horizontally (parallel to the wafer W surface). On the lowersurface of scale plate 83 in an area at least slightly larger than waferW, a two-dimensional grating (hereinafter, simply referred to as agrating) RG is provided. Grating RG includes a reflection typediffraction grating (X diffraction grating) whose period direction is inthe X-axis direction and a reflection type diffraction grating (Ydiffraction grating) whose period direction is in the Y-axis direction.The pitch of the grid lines of the X diffraction grating and the Ydiffraction grating is set, for example, to 1 μm.

Main section 81 and scale plate 83 are preferably formed of a materialhaving a thermal expansion coefficient which is the same or about thesame, and the material is preferably a material having a low thermalexpansion coefficient. Further, the surface of grating RG can beprotected, being covered by a protective member, such as, for example, acover glass which is made of a transparent material having transmittanceto light and a low thermal expansion coefficient. Incidentally, gratingRG may employ any structure as long as grating RG is arrangedperiodically in two different directions, and the periodic directions donot have to coincide with the X direction and the Y direction, such asfor example, the periodic directions being rotated by 45 degrees to theX direction and the Y direction.

In the present embodiment, while fine movement stage WFS has mainsection 81 and wafer table WTB, for example, wafer table WTB can bedriven by the actuator previously described, without main section 81provided. Further, fine movement stage WFS only has to have a mountingarea of wafer W on a part of its upper surface, and can be referred toas a holding section, table, or moving section of wafer stage WST.

The pair of mover sections 82 a and 82 b each have a housing whose YZsection is rectangular frame shaped fixed to one end and the other endin the X-axis direction of main section 81, respectively. Hereinafter,for the sake of convenience, these housings will be expressed ashousings 82 a and 82 b, using the same reference signs as mover sections82 a and 82 b.

Housing 82 a has a space (opening section) having a rectangular YZ shapeelongated in the Y-axis direction and whose size (length) in the Y-axisdirection and size (height) in the Z-axis direction are both slightlylarger than stator section 93 a. Into the space of housing 82 a, theedge on the −X side of stator section 93 a of coarse movement stage WCSis inserted in a non-contact manner. Inside housing 82 a in an upperwall section 82 a ₁ and a bottom wall section 82 a ₂, magnet units MUa₁and MUa₂ are provided.

Mover section 82 b is similarly structured to mover section 82 a, whilebeing horizontally symmetric. Into the space of housing (mover section)82 b, the edge on the +X side of stator section 93 b of coarse movementstage WCS is inserted in a non-contact manner. Inside housing 82 b in anupper wall section 82 b ₁ and a bottom wall section 82 b, magnet unitsMUb₁ and MUb₂ which are structured similarly to magnet units MUa₁ andMUa₂ are provided.

Coil units CUa and CUb described above are housed inside stator sections93 a and 93 b, respectively, corresponding to magnet units MUa₁ andMUa₂, and MUb₁ and MUb₂, respectively.

The structures of magnet units MUa₁ and MUa₂, and MUb₁ and MUb₂, andcoil units CUa and CUb are disclosed in detail in, for example, U.S.Patent Application Publication No. 2010/0073652, U.S. Patent ApplicationPublication No. 2010/0073653 and the like.

In the present embodiment, fine movement stage driving system 52A (referto FIG. 16) is structured, including the pair of magnet units MUa₁ andMUa₂ which mover section 82 a has and coil unit CUa which stator section93 a has, and the pair of magnet units MUb₁ and MUb₂ which mover section82 b has and coil unit CUb which stator section 93 b has that arepreviously described, that supports fine movement stage WFS bylevitation with respect to coarse movement stage WCS in a non-contactstate, and also drives fine movement stage WFS in directions of sixdegrees of freedom in a non-contact manner, similarly to the U.S. PatentApplication Publication No. 2010/0073652 and U.S. Patent ApplicationPublication No. 2010/0073653 described above.

Incidentally, in the case of using a magnetic levitation type planarmotor as coarse movement stage driving system 51A (refer to FIG. 16),because fine movement stage WFS can be finely driven in each of theZ-axis, the θx, and the θy directions integrally with coarse movementstage WCS by the planar motor, fine movement stage driving system 52Acan employ a structure where fine movement stage WFS is drivable in eachof the X-axis, the Y-axis, and the θz directions, that is, in directionsof three degrees of freedom within the XY-plane. Besides this, forexample, to each of the pair of side wall sections 92 a and 92 b ofcoarse movement stage WCS, electromagnets can be provided in pairs, eachfacing the oblique side section of the octagonal shape of fine movementstage WFS, and in fine movement stage WFS, a magnetic body member can beprovided facing each electromagnet. Because this allows fine movementstage WFS to be driven within the XY-plane by the magnetic force of theelectromagnet, mover sections 82 a and 82 b and stator sections 93 a and93 b can structure a pair of Y-axis linear motors.

In the center of the upper surface of wafer table WTB, a wafer holder(not shown) is provided which holds wafer W by vacuum chucking and thelike. The wafer holder can be integrally formed with wafer table WTB, orcan be fixed to wafer table WTB, for example, via an electrostatic chuckmechanism, a clamp mechanism and the like, or by adhesion and the like.Here, although it is omitted in the drawings in FIG. 2B and the like, inmain section 81, a plurality of, for example, three vertical movementpins 140 (refer to FIG. 6A), which are vertically movable via holesprovided in wafer table WTB and the wafer holder are provided. The threevertical movement pins 140 are vertically movable so that their uppersurfaces vertically move between a first position above the uppersurface of the wafer holder (wafer table WTB) and a second positionbelow the upper surface of the wafer holder (wafer table WTB). The threevertical movement pins 140 are driven by main controller 20 via a driver142 (refer to FIG. 16).

On the outer side the wafer holder (mounting area of the wafer) on theupper surface of wafer table WTB, as shown in FIG. 2A, a circularopening slightly larger than the wafer holder is formed in the center,and a plate (liquid repellent plate) 28 is provided that has arectangular outer shape (outline). Plate 28 is made of a material with alow thermal expansion coefficient, such as, for example, glass orceramics (e.g., Zerodur (product name) of Schott AG, Al₂O₃ or TiC andthe like), and on its surface, a liquid repellent processing to liquidLq is applied. To be specific, a liquid repellent film is formed of, forexample, a fluorine-based resin material such as a fluororesin materialor polytetrafluoroethylene (Teflon (registered trademark)), anacrylic-based resin material, a silicon-based resin material or thelike. Incidentally, plate 28 is fixed to the upper surface of wafertable WTB so that its entire (or a part of the) surface is flush withthe surface of wafer W.

Plate 28 is positioned in the center in the X-axis direction of wafertable WTB, and has a first liquid repellent area 28 a having arectangular outer shape (outline) and a circular opening formed in thecenter, and a pair of second liquid repellent areas 28 b having arectangular shape and being positioned on the +X side edge and the −Xside edge of wafer table WTB, with the first liquid repellent area 28 ain between in the X-axis direction. Incidentally, in the presentembodiment, because water is used as liquid Lq as is previouslydescribed, hereinafter, the first liquid repellent area 28 a and thesecond liquid repellent area 28 b will also be referred to as a firstwater repellent plate 28 a and a second water repellent plate 28 b,respectively.

In the vicinity of the edge on the +Y side of the first water repellentplate 28 a, a measurement plate 30 is provided. In this measurementplate 30, a fiducial mark FM is provided in the center, and a pair ofaerial image measurement slit patterns (slit shaped measurementpatterns) SL is provided, with fiducial mark FM in between. And,corresponding to each aerial image measurement slit pattern SL, a lighttransmitting system (not shown) is provided which guides illuminationlight IL passing through the slit patterns to the outside of wafer stageWST (a light receiving system provided in measurement stage MST to bedescribed later on). Measurement plate 30 is placed, for example, withinan opening of plate 28 different from the opening where the wafer holderis placed, and a gap between measurement plate 30 and plate 28 isblocked so that the liquid does not flow into wafer table WTB by a sealmember and the like. Further, measurement plate 30 is provided on wafertable WTB so that its surface is substantially flush with the surface ofplate 28. Incidentally, at least one opening section (light transmittingsection) different from slit pattern SL can be formed on measurementplate 30, and by detecting illumination light IL passing through theopening section via projection optical system PL and the liquid with asensor, for example, optical properties of projection optical system PL(including wavefront aberration and the like) and/or properties ofillumination light IL (including light amount, illuminance distributionwithin exposure area IA previously described and the like) can bemeasured.

On the pair of the second water repellent plates 28 b, scales 39 ₁ and39 ₂ are formed, respectively, for the first to fourth top side encodersystems 80A to 80D. To describe this in detail, scales 39 ₁ and 39 ₂ areeach structured by a reflection type two-dimensional diffraction gratingwhich is a combination of, for example, a diffraction grating whoseperiod direction is in the Y-axis direction and a diffraction gratingwhose period direction is in the X-axis direction. The pitch of the gridlines of the two-dimensional diffraction grating is set to, for example,1 μm for both the Y-axis direction and the X-axis direction. Further,because the pair of the second water repellent plates 28 b each havescales (two-dimensional gratings) 39 ₁ and 39 ₂, the second waterrepellent plates are referred to as a grating member, a scale plate, ora grid plate, and in the present embodiment, for example, atwo-dimensional grating is formed on a surface of a glass plate having alow thermal expansion coefficient, and a liquid repellent film is formedso as to cover the two-dimensional grating. Incidentally, in FIG. 2A,for the sake of convenience in the drawings, the pitch of the grating isillustrated larger than the actual pitch. This is the same in otherdrawings as well. Further, the two-dimensional grating can have anystructure as long as the grating is arranged periodically in twodifferent directions, and the periodic directions do not have tocoincide with the X direction and the Y direction, and for example, theperiodic direction can be rotated by 45 degrees with respect to the Xdirection and the Y direction.

Incidentally, to protect the diffraction grating of the pair of thesecond water repellent plates 28 b, it is also effective to cover thediffraction grating with a low thermal expansion coefficient glass platethat has water repellency. Here, as the glass plate, a plate whosethickness is around the same as the wafer, such as for example, a platehaving a 1 mm thickness, can be used, and as an example, the plate isinstalled on the upper surface of wafer table WTB so that the surface ofthe glass plate is at substantially the same height (flush) as the wafersurface. Further, in the case the pair of the second water repellentplates 28 b is placed away from wafer W to an extent where the pair ofthe second water repellent plates 28 b is not in contact with the liquidof the liquid immersion area previously described at least during theexposure operation of wafer W, the surface of the pair of the secondwater repellent plates 28 b does not have to be liquid repellent. Thatis, the pair of the second water repellent plates 28 b can each simplybe a grating member on which a scale (two-dimensional grating) isformed.

In the present embodiment, while plate 28 is provided on wafer tableWTB, plate 28 does not have to be provided, in this case, a recessportion in which the wafer holder is placed can be provided on the uppersurface of wafer table WTB, and for example, a pair of grating memberspreviously described whose surface is not liquid repellent can be placedon wafer table WTB in the X direction, with the recess section inbetween. As previously described, this pair of grating members should beplaced apart from the recess section to an extent so that the pair ofgrating members is not in contact with the liquid of the liquidimmersion area. Further, the recess can be formed so that the surface ofwafer W held by the wafer holder within the recess section becomessubstantially flush with the upper surface of wafer table WTB.Incidentally, the whole, or a part of the upper surface of wafer tableWTB (including at least a periphery area surrounding the recess section)can be liquid repellent. Further, in the case the pair of gratingmembers on which scales (two-dimensional grating) 39 ₁ and 39 ₂ areformed is placed in proximity to the recess section, the pair of thesecond water repellent plates 28 previously described can be used,instead of the pair of grating members whose surface is not liquidrepellent.

Incidentally, near the edge the scales of each of the second waterrepellent plates 28 b, positioning patterns not shown are provided,respectively, which are used to decide a relative position between anencoder head to be described later on and the scales. This positioningpattern is structured, for example, of grid lines with differentreflectivity, and when the encoder head scans this positioning pattern,the intensity of the output signal of the encoder changes. Therefore, athreshold value is decided in advance, and the position where theintensity of the output signal exceeds the threshold value is detected.The relative position between the encoder head and the scale is set withthe detected position serving as a reference. Further, as describedabove, in the present embodiment, because fine movement stage WFS isequipped with wafer table WTB, in the description hereinafter, finemovement stage WFS including wafer table WTB will also be described aswafer table WTB.

Next, although it is out of sequence, chuck unit 120 will be described.Chuck unit 120 is used to hold a wafer which is not yet exposed aboveits loading position prior to loading the wafer on wafer table WTB, andto load the wafer on wafer table WTB.

Chuck unit 120, as shown in FIG. 1, is equipped with a drive section 122fixed to the lower surface of main frame BD via a vibration isolationmember which is not shown, and a chuck main section 130 which isvertically moved by drive section 122. FIG. 6A schematically shows afront view of chuck unit 120 (when viewed from the −Y direction), andFIG. 6B schematically shows a planar view of chuck unit 120,respectively. Drive section 122 incorporates a motor, and drives chuckmain section 130 via a vertical movement shaft 122 a in a verticaldirection (Z-axis direction) as shown in FIG. 6A.

Chuck main section 130 is equipped with a cool plate 123 consisting of aplate shaped member which is circular in a planar view having apredetermined thickness and whose upper surface is fixed to the lowerend of vertical movement shaft 122 a, a Bernoulli chuck (or also calleda float chuck) 124 whose upper surface is fixed to the lower surface ofcool plate 123, and the like.

Cool plate 123 is used to control the temperature of the wafer to apredetermined temperature, and for example, the wafer is controlled to apredetermined temperature by a piping and the like being provided insidethe plate, and a liquid whose temperature is controlled to apredetermined temperature flowing in the piping. On both ends in theX-axis direction of cool plate 123, a pair of guide sections 125 isprovided. In each of the pair of guide sections 125, a guide hole 125 ais formed consisting of a through hole which is running in the verticaldirection.

Inside guide hole 125 a formed in one of guide sections 125, a shaft 126extending in the vertical direction is inserted with a predeterminedinterval formed. The upper end of shaft 126 is exposed above guidesection 125, and is connected to a vertical movement rotation drivingsection 127. Vertical movement rotation driving section 127 is attachedto main frame BD via an attachment member not shown. The lower end ofshaft 126 is exposed below guide sections 125, and a support plate 128extending in an uniaxial direction within the XY-plane (extending in theX-axis direction in FIG. 6A) is fixed to its lower end surface.Incidentally, to prevent dust from being generated, it is preferable toplace a non-contact bearing such as an air bearing at a plurality ofplaces on the inner circumference surface of guide hole 125 a. The uppersurface near one end in the longitudinal direction of support plate 128is fixed to shaft 126. The other end in the longitudinal direction ofsupport plate 128 is rotationally driven by vertical movement rotationdriving section 127 in the θz direction between a first rotatingposition which faces the outer circumference of Bernoulli chuck 124 anda second rotating position which does not face Bernoulli chuck 124, andis driven in the vertical direction as well in predetermined strokes.

Vertical movement rotation driving section 127, shaft 126, and supportplate 128 are also provided in the other guide section 125 side, in theplace and structure similar to the description above.

Bernoulli chuck 124 consists of a plate shaped member which issubstantially the same size as cool plate 123 but much thinner than coolplate 123. To three places on the outer circumference surface ofBernoulli chuck 124, an imaging device 129, such as, for example, a CCDand the like, is attached in an embedded state (in FIG. 6A and the like,only one of the imaging devices is shown representatively). One of thethree imaging devices 129 is placed at a position facing a notch (cut ina V-shape, not shown) of wafer W in a state where the center of wafer Wsubstantially coincides with the center of Bernoulli chuck 124, and theremaining two imaging devices 129 are each placed at a position facing apart of the outer circumference of wafer W in a state where the centerof wafer W substantially coincides with the center of Bernoulli chuck124. Further, in Bernoulli chuck 124, for example, a gap sensor which isnot shown consisting of an electrostatic capacitance sensor is provided,and its output is supplied to main controller 20.

Bernoulli chuck is a chuck, as is well known, which utilizes theBernoulli effect to locally increase the flow velocity of a fluid (forexample, air) that blows out, and fixes (hereinafter also appropriatelyreferred to as supports, holds, or suctions) a subject in a non-contactmanner. Here, the Bernoulli effect refers to an effect of theBernoulli's theory (principle) in which the pressure of a fluiddecreases when the flow velocity of the fluid increases that is exertedon fluid machinery and the like. In the Bernoulli chuck, the holdingstate (suction/levitation state) is decided according to the weight ofthe subject which is suctioned (fixed), and the flow velocity of thefluid that blows out from the chuck. That is, in the case the size ofthe subject is known, the size of the gap between the chuck upon holdingand the subject to be held is decided according to the flow velocity ofthe fluid blowing out from the chuck. In the present embodiment,Bernoulli chuck 124 is used to suction (support or hold) a wafer (W).Movement of the wafer in the Z-axis direction, and the θx and θydirections is limited by the wafer being held by suction by Bernoullichuck 124, while movement in the X-axis direction, the Y-axis directionand the θz direction is limited by a frictional force occurring whenbeing in contact and supported from below at two places near the outercircumference on the lower surface (rear surface) of the pair of supportplates 128 in a state where the wafer is held by suction by Bernoullichuck 124.

Incidentally, the chuck used is not limited to the chuck utilizing theBernoulli effect, and a chuck which holds a wafer in a non-contactmanner without utilizing the Bernoulli effect can also be used. In theembodiment, such chucks are included (referred to in general) as aBernoulli chuck.

Imaging signals of imaging device 129 described above are sent to asignal processing system 116 (refer to FIG. 16), and by using the methoddisclosed in, for example, U.S. Pat. No. 6,624,433 and the like, signalprocessing system 116 detects three places of the wafer in the peripheryincluding the cut (such as the notch) and obtains positional deviationof wafer W in the X-axis direction and the Y-axis direction and rotation(θz rotation) errors. And, information of the positional deviation androtation errors is supplied to main controller 20 (refer to FIG. 16). Inthe present embodiment, while the three imaging devices 129 are used asa pre-alignment device for performing position measurement of wafer Wheld by Bernoulli chuck 124, the pre-alignment device is not limited tothe imaging devices, and other sensors such as for example, a lightamount sensor and the like can also be used. Further, while thepre-alignment device is provided in Bernoulli chuck 124, for example,one of a light-emitting section and a light-receiving sectionstructuring the pre-alignment device can be provided in Bernoulli chuck124, and the other can be provided in wafer stage WST or in main frameBD and the like. Furthermore, at least a part of the light-emittingsection and a light-receiving section, such as for example, a lightsource and/or a sensor (detector) and the like can be provided not inBernoulli chuck 124, but in other places such as for example, in themain section frame and the like.

Drive section 122, Bernoulli chuck 124, a pair of vertical movementrotation driving sections 127 and the like of chuck unit 120 arecontrolled by main controller 20 (refer to FIG. 16). Each operationperformed by main controller 20 using chuck unit 120 will be describedlater in the description.

Next, measurement stage MST will be described. FIGS. 3A, 3B, and 3C showa front view (when viewed from the −Y direction), a side view (whenviewed from the −X direction), and a planar view (when viewed from +Zdirection) of measurement stage MST, respectively. As shown in theseFIGS. 3A to 3C, measurement stage MST is equipped with a slider section60 which has a rectangular shape and whose longitudinal direction is inthe X-axis direction in a planar view (when viewed from the +Zdirection), a support section 62 consisting of a rectangularparallelepiped member fixed to the end on the +X side on the uppersurface of slider section 60, and a measurement table MTB which has arectangular plate shape and is supported in a cantilevered manner onsupport section 62, and is finely driven, for example, in directions ofsix degrees of freedom (or directions of three degrees of freedom withinthe XY-plane), via a measurement table driving system 52B (refer to FIG.16).

On the bottom surface of slider section 60, although it is not shown, amagnet unit consisting of a plurality of permanent magnets is provided,which structures a measurement stage driving system 51B (refer to FIG.16) consisting of an electromagnetically (Lorentz force) driven planarmotor, along with a coil unit (coil 17) of base board 12. On the bottomsurface of slider section 60, in the periphery of the magnet unitdescribed above, a plurality of air bearings (not shown) is fixed.Measurement stage MST is supported by levitation above base board 12 bythe air bearings previously described via a predetermined clearance gap(gap, clearance), such as for example, a clearance gap of around severalμm, and is driven in the X-axis direction and the Y-axis direction bymeasurement stage driving system 51B. Incidentally, while coarsemovement stage driving system 51A and measurement stage driving system51B share the same coil unit, in the embodiment, for the sake ofconvenience, a concept of separately showing coarse movement stagedriving system 51A and measurement stage driving system 51B is employed.In practice, because different coils 17 in the coil unit are used forthe drive of wafer stage WST and measurement stage MST, respectively,this concept does not cause any problems. Incidentally, althoughmeasurement stage MST employs the air levitation method, for example,measurement stage MST can employ a magnetic floating method.

In measurement table MTB, various measurement members are provided. Assuch measurement members, for example, as shown in FIG. 3C, anilluminance irregularity sensor 95 which has a pin-hole shaped lightreceiving section that receives illumination light IL on an image planeof projection optical system PL, an aerial image measuring instrument 96which measures an aerial image (projection image) of a pattern projectedby projection optical system PL, a wavefront aberration measuringinstrument 97 which employs a Shack-Hartmann (Shack-Hartmann) methodwhose details are disclosed in, for example, International PublicationNo. 03/065428 and the like, an illuminance monitor 98 which has a lightreceiving section of a predetermined area that receives illuminationlight IL on an image plane of projection optical system PL and the likeare provided.

As illuminance irregularity sensor 95, a sensor having a structuresimilar to the one disclosed in, for example, U.S. Pat. No. 4,465,368and the like can be used. Further, as aerial image measuring instrument96, an instrument having a structure similar to the one disclosed in,for example, U.S. Patent Application Publication No. 2002/0041377 andthe like can be used. As wavefront aberration measuring instrument 97,the one disclosed in, for example, International Publication 99/60361(corresponding European Patent No. 1079223) can be used. As illuminancemonitor 98, a monitor having a structure similar to the one disclosedin, for example, U.S. Patent Application Publication No. 2002/0061469and the like can be used.

Further, in measurement table MTB, in a placement that can face the pairof light transmitting systems (not shown) previously described, a pairof light receiving systems (not shown) is provided. In the presentembodiment, an aerial image measurement device 45 (refer to FIG. 16) isstructured in which each light transmitting system (not shown) guidesillumination light IL having passed through each aerial imagemeasurement slit pattern SL of measurement plate 30 on wafer stage WST,and a photodetection element of each light receiving system (not shown)within measurement stage MST receives the light, in a state where waferstage WST and measurement stage MST are close within a predetermineddistance in the Y-axis direction (including a state in contact).

Incidentally, in the embodiment, while the four measurement members (95,96, 97, and 98) were provided on measurement table MTB, the type and/orthe number of the measurement members are/is not limited to this. As themeasurement members, for example, a transmittance measuring instrument,and/or a measuring instrument which observes local liquid immersiondevice 8 previously described, such as for example, nozzle unit 32 (ortip lens 191) and the like, can also be used. Furthermore, a memberdifferent from the measurement members, such as, for example, a cleaningmember used to clean nozzle unit 32, tip lens 191 and the like can alsobe installed in measurement stage MST.

Incidentally, in the embodiment, corresponding to performing the liquidimmersion exposure of wafer W by exposure light (illumination light) ILvia projection optical system PL and liquid (water) Lq, in illuminanceirregularity sensor 95, aerial image measuring instrument 96, wavefrontaberration measuring instrument 97, and illuminance monitor 98 describedabove used in measurement using illumination light IL, illuminationlight IL is to be received via projection optical system PL and thewater. Further, each sensor can have a part of the sensor, such as forexample, a light receiving surface (light receiving section) whichreceives illumination light via an optical system and water and a partof the optical system placed at measurement table MTB, or the wholesensor can be placed at measurement table MTB.

On the upper surface of measurement table MTB, a plate 63 is fixed,consisting of a transparent member whose surface is covered with aliquid repellent film (water repellent film). Plate 63 is made of amaterial similar to plate 28 previously described. On the lower surface(surface on the −Z side) of measurement table MTB, a grating RGa similarto grating RG previously described is provided.

Incidentally, in the case measurement stage driving system 51B isstructured using a magnetic levitation type planar motor, themeasurement stage can be, for example, a stand-alone stage which ismovable in directions of six degrees of freedom. Further, plate 63 doesnot have to be provided on measurement table MTB. In this case, on theupper surface of measurement table MTB, a plurality of openings in whichlight-receiving surfaces (light transmitting sections) of the pluralityof sensors previously described are each placed should be formed, andfor example, at least a part of the sensors including thelight-receiving surfaces can be provided on measurement table MTB sothat the light-receiving surfaces within the opening becomessubstantially flush with the upper surface of measurement table MTB.

Position information of measurement stage MST within the XY-plane ismeasured by main controller 20, using measurement stage positionmeasuring system 16B (refer to FIGS. 1 and 16) consisting of a similarinterferometer system to wafer stage position measurement system 16A.

Measurement stage MST is engageable to measurement arm 71A from the −Xside, and in the engaged state, measurement table MTB is positionedright above measurement arm 71A. At this point, position information ofmeasurement table MTB is measured by a plurality of encoder heads whichirradiate a measurement beam on grating RGa that measurement arm 71A tobe described later on has.

Further, measurement table MTB can be as near as a distance of, forexample, around 300 μm or be in contact from the +Y side to/with wafertable WTB (fine movement stage WFS) supported by coarse movement stageWCS, and in the approaching or contact state, forms a surface (forexample, refer to FIG. 27) that appears to be completely flat, alongwith the upper surface of wafer table WTB. Measurement table MTB(measurement stage MST) is driven by main controller 20 via measurementstage driving system 51B, and performs delivery of liquid immersion area(liquid Lq) with wafer table WTB. That is, a part of a border (boundary)which sets the liquid immersion space formed below projection opticalsystem PL is switched from one of the upper surface of wafer table WTBand the upper surface of measurement table MTB to the other of the uppersurface of wafer table WTB and the upper surface of measurement tableMTB. Incidentally, the delivery of the liquid immersion area (liquid Lq)between measurement table MTB and wafer table WTB will be furtherdescribed later on.

Next, the structure of the first fine movement stage positionmeasurement system 110A (refer to FIG. 16), which is used to measureposition information of fine movement stage WFS held movable by coarsemovement stage WCS located at exposure station 200, will be described.

The first back side encoder system 70A of the first fine movement stageposition measurement system 110A, as shown in FIG. 1, is equipped withmeasurement arm 71A which is inserted into a space provided insidecoarse movement stage WCS in a state where wafer stage WST is placedbelow projection optical system PL.

Measurement arm 71A, as is shown in FIG. 7, has an arm member 71 ₁supported by main frame BD in a cantilevered state via support member72A, and an encoder head (at least a part of the optical system) to bedescribed later on housed inside arm member 71 ₁. That is, a headsection (including at least a part of the optical system) of the firstback side encoder system 70A is supported by a measurement member (alsoreferred to as a support member or a metrology arm) including arm member71 ₁ of measurement arm 71A and support member 72A so that the headsection is placed lower than grating RG of wafer table WTB. This allowsthe measurement beam of the first back side encoder system 70A to beirradiated on grating RG from below. Arm member 71 ₁, as shown enlargedin FIG. 8A, consists of a hollow columnar member having a rectangularcross section whose longitudinal direction is in the Y-axis direction.The size in the width direction (the X-axis direction) of arm member 71₁, for example, as shown in FIG. 19, is widest near the base end, andthe width narrows gradually from the base end toward the tip end side toa position slightly to the base end from the center in the longitudinaldirection, and the width is substantially constant from the positionslightly to the base end from the center in the longitudinal directionto the tip end. In the present embodiment, while the head section of thefirst back side encoder system 70A is placed in between grating RG ofwafer table WTB and the surface of base board 12, for example, the headsection can be place below base board 12.

Arm member 71 ₁ is made of a material having a low thermal expansioncoefficient, preferably a material of zero expansion (for example,Zerodur (product name) of Schott AG and the like), and at the tip end,as shown in FIG. 7, for example, a mass damper (also called a dynamicmass damper) 69 having a specific resonance frequency of around 100 Hzis provided. Here, the mass damper is an elastic member such as, forexample, a pendulum structured with a spring and a weight, and when thisis attached, in the case vibration is applied externally to a structure(in this case, arm member 71 ₁), if the vibration frequency is the sameas the resonance of the mass damper, the weight resonantly vibrates andalternatively absorbs the vibration energy of the structure (in thiscase, arm member 71 ₁). This can reduce the vibration of a particularfrequency of the structure (in this case, arm member 71 ₁).Incidentally, the vibration of arm member 71 ₁ can be suppressed orprevented by a vibration suppressing member other than the mass damper.Further, this vibration suppressing member is one of a compensatingdevice which compensates measurement errors of the first back sideencoder system 70A which occurs due to the vibration of arm member 71 ₁,and the first top side encoder system 80A to be described later on isalso one of a compensating device.

Arm member 71 ₁ has high rigidity because of being hollow and having awide base end, and because the shape in a planar view is set in themanner described above, in a state where wafer stage WST is placed belowprojection optical system PL, wafer stage WST moves in a state where thetip of arm member 71 ₁ is inserted into the space of coarse movementstage WCS, and on this movement, this structure can keep arm member 71 ₁from interfering the movement of the stage. Further, an optical fiber ofa light transmitting side (light source side) and a light receiving side(detector side) and the like, which is used for transmitting light(measurement beam) between an encoder head to be described later on,runs through the inside the hollow space of arm member 71 ₁.Incidentally, arm member 71 ₁ can be formed, for example, of a memberhaving a portion where only the optical fiber runs through is hollow,and other portions are solid.

As previously described, in the state where wafer stage WST is placedbelow projection optical system PL, the tip of arm member 71 ₁ ofmeasurement arm 71A is inserted into the space within coarse movementstage WCS, and as shown in FIGS. 1 and 7, its upper surface facesgrating RG (not shown in FIGS. 1 and 7, refer to FIG. 2B and the like)provided on the lower surface of fine movement stage WFS (to be moreprecise, the lower surface of main section 81). The upper surface of armmember 71 ₁ is placed substantially parallel to the lower surface offine movement stage WFS, in a state where a predetermined clearance gap(gap, clearance), for example, a clearance of around several mm, isformed with the lower surface of fine movement stage WFS.

The first back side encoder system 70A, as shown in FIG. 17, includes apair of three-dimensional encoders 73 a and 73 b which each measures aposition of fine movement stage WFS in each of the X-axis, the Y-axis,and the Z-axis directions, an XZ encoder 73 c which measures a positionof fine movement stage WFS in the X-axis and the Z-axis directions, anda YZ encoder 73 d which measures a position of fine movement stage WFSin the Y-axis and the Z-axis directions.

XZ encoder 73 c and YZ encoder 73 d are equipped with a two-dimensionalhead whose measurement direction is in the X-axis and the Z-axisdirections and a two-dimensional head whose measurement direction is inthe Y-axis and the Z-axis directions, respectively, housed inside thearm member of measurement arm 71A, respectively. Hereinafter, for thesake of convenience, the two-dimensional heads that XZ encoder 73 c andYZ encoder 73 d respectively have will be described as XZ head 73 c andYZ head 73 d, using the same reference sign as each of the encoders. Aseach of such XZ head 73 c and YZ head 73 d, an encoder head(hereinafter, appropriately shortened to as a head) having a structuresimilar to the displacement measurement sensor head disclosed in, forexample, U.S. Pat. No. 7,561,280, can be used. Further, the pair ofthree-dimensional encoders 73 a and 73 b is equipped with athree-dimensional head whose measurement direction is in the X-axis, theY-axis, and the Z-axis directions, each housed inside arm member 71 ₁ ofmeasurement arm 71A. Hereinafter, for the sake of convenience, thethree-dimensional heads that three-dimensional encoders 73 a and 73 bhave, respectively, will be described as three-dimensional heads 73 aand 73 b, using the same reference sign as each of the encoders. Asthree-dimensional heads 73 a and 73 b, for example, a three-dimensionalhead which is structured combining XZ head 73 c and YZ head 73 d so thatthe measurement point (detection point) of each of the heads is at thesame point, and measurement in the X-axis direction, the Y-axisdirection, and the Z-axis direction is also possible, can be used.

FIG. 8A shows a perspective view of the tip of arm member 71 ₁, and FIG.8B shows a planar view of the upper surface of the tip of arm member 71₁ when viewed from the +Z direction. As shown in FIGS. 5A and 8B, thepair of three-dimensional heads 73 a and 73 b are placed at positionssymmetrical to center line CL of arm member 71 ₁. One ofthree-dimensional heads 73 a irradiates measurement beams LBxa₁ andLBxa₂ (refer to FIG. 8A) on grating RG from two points (refer to thewhite circles in FIG. 5B) which are on a straight line LX1 parallel tothe X-axis, at positions of an equal distance (referred to as a distancea) from a straight line LY1 parallel to the Y-axis that is apredetermined distance away from center line CL. Further,three-dimensional head 73 a irradiates measurement beams LBya₁ and LBya₂on grating RG from two points that are at positions on straight line LY1and of distance a from straight line LX1. Measurement beams LBxa₁ andLBxa₂ are irradiated on the same irradiation point on grating RG, andfurther, measurement beams LBya₁ and LBya₂ are also irradiated on theirradiation point. In the present embodiment, the irradiation point ofmeasurement beams LBxa₁ and LBxa₂ and measurement beams LBya₁ and LBya₂,or in other words, the detection point (refer to reference sign DP1 inFIG. 8B) of the three-dimensional head 73 a coincides with the exposureposition which is the center of irradiation area (exposure area) IA ofillumination light IL irradiated on wafer W (refer to FIG. 1). Here,straight line LY1 coincides with reference axis LV previously described.

Three-dimensional head 73 b irradiates measurement beams LBxb₁ and LBxb₂on grating RG from two points (refer to the white circles in FIG. 8B)located on straight line LX1 at positions that are away from a straightline LY2 symmetrical to straight line LY1 regarding center line CL bydistance a. Further, three-dimensional head 73 b irradiates measurementbeams LByb₁ and LByb₂ on grating RG from two points located on straightline LY2 at positions that are away from straight line LX1 by distancea. Measurement beams LBxb₁ and LBxb₂ are irradiated on the sameirradiation point on grating RG, and further, measurement beams LByb₁and LByb₂ are also irradiated on the irradiation point. The irradiationpoint of measurement beams LBxb₁ and LBxb₂ and measurement beams LByb₁and LByb₂, that is to say, the detection point (refer to reference signDP2 in FIG. 8B) of three-dimensional head 73 b is a point apredetermined distance away to the −X side of the exposure position.

XZ head 73 c is placed at a position a predetermined distance away tothe +Y side of three-dimensional head 73 a. XZ head 73 c, as shown inFIG. 88, irradiates measurement beams LBxc₁ and LBxc₂ each shown inbroken lines in FIG. 8A on a common irradiation point on grating RG fromtwo points (refer to the white circles in FIG. 8B) which are on astraight line LX2 that is parallel to the X-axis and is positioned apredetermined distance to the +Y side of straight line LX1, at positionsthat are each away from straight line LY1 by distance a. The irradiationpoint of measurement beams LBxc₁ and LBxc₂, that is to say, thedetection point of XZ head 73 c is shown as reference sign DP3 in FIG.8B.

YZ head 73 d is placed at a position a predetermined distance away tothe +Y side of three-dimensional head 73 b. YZ head 73 d, as shown inFIG. 8B, irradiates measurement beams LByc₁ and LByc₂ each shown inbroken lines in FIG. 8A on a common irradiation point on grating RG fromtwo points (refer to the white circles in FIG. 8B) which are placed onstraight line LY2, at positions that are away from straight line LX2 bydistance a. The irradiation point of measurement beams LByc₁ and LByc₂,that is to say, the detection point of YZ head 73 d is shown asreference sign DP4 in FIG. 8B.

In the first back side encoder system 70A, three-dimensional encoders 73a and 73 b are structured by the pair of three-dimensional heads 73 aand 73 b, respectively, which measure the position of fine movementstage WFS in the X-axis, the Y-axis, and the Z-axis directions using theX diffraction grating and the Y diffraction grating of grating RG, XZencoder 73 c is structured by XZ head 73 c which measures the positionof fine movement stage WFS in the X-axis and the Z-axis directions usingthe X diffraction grating of grating RG, and YZ encoder 73 d isstructured by YZ head 73 d which measures the position of fine movementstage WFS in the Y-axis and the Z-axis directions using the Ydiffraction grating of grating RG.

The output of encoders 73 a, 73 b, 73 c, and 73 d of the first back sideencoder system 70A is supplied to main controller 20 via switchingsection 150A to be described later on (refer to FIGS. 16, 17 and thelike).

Now, measurement of the position of fine movement stage WFS indirections of six degrees of freedom using the first back side encodersystem 70A and measurement of the difference of the XYZ grids that areperformed by main controller 20 when the output of the first back sideencoder system 70A is supplied to main controller 20, via switchingsection 150A, will be described, based on FIGS. 10A to 12B.

Here, as a premise, as shown in FIG. 10A, measurement values ofthree-dimensional encoders 73 a and 73 b are to be (X1,Y1,Z1) and(X2,Y2,Z2), respectively, and measurement values of XZ encoder 73 c areto be (X3, Z3), and measurement values of YZ encoder 73 d are to be(Y3,Z4).

In the present embodiment, as an example, as shown blackened in FIG.10B, X1, Y1, Y2, Z1, Z2, and Z3 are used for position measurement offine movement stage WFS in directions of six degrees of freedom (in eachof the X-axis, the Y-axis, the Z-axis, the θx, the θy, and the θzdirections). To be specific, main controller 20 uses X1, Y1, and Z1 tocalculate the position of fine movement stage WFS in the X-axis, theY-axis, and the Z-axis directions, uses Y1 and Y2 to calculate theposition of fine movement stage WFS in the θz direction, uses Z1 and Z2to calculate the position of fine movement stage WFS in the θydirection, and uses Z1 and Z3 to calculate the position of fine movementstage WFS in the θx direction.

Here, in the present embodiment, because detection point DP1 ofthree-dimensional head 73 a coincides with the exposure position, inorder to measure the position of fine movement stage WFS in the X-axis,the Y-axis, and the Z-axis directions at detection points DP1, theposition of fine movement stage WFS in the X-axis, the Y-axis, and theZ-axis directions is calculated using X1, Y1, and Z1. Accordingly, forexample, in the case the exposure position coincides with a point in thecenter of detection points DP1 and DP2 of the pair of three-dimensionalheads 73 a and 73 b, main controller 20 can obtain the position of finemovement stage WFS in the X-axis, the Y-axis, and the Z-axis directions,based on an average value of X1 and X2, an average value of Y1 and Y2,and an average value of Z1 and Z2.

Further, concurrently with the position measurement of fine movementstage WFS in directions of six degrees of freedom described above, maincontroller 20 performs a difference measurement described below, andobtains X, Y, and Z grids (grid errors) of a coordinate system of thefirst back side encoder system 70A. That is, as shown in FIGS. 10B and11A, main controller 20 obtains a deviation ΔX/δx corresponding to the Xposition of the X grid using X1 and X2, and as shown in FIGS. 10B and11B, obtains a deviation ΔX/δy corresponding to the Y position of the Xgrid using X1 and X3. By this operation, a ΔX map as is shown in FIG.11C can be obtained.

Similarly, as shown in FIG. 10B, main controller 20 obtains a deviationΔY/δy corresponding to the Y position of the Y grid using Y2 and Y3,obtains a deviation ΔZ/δx corresponding to the X position of the Z gridusing Z3 and Z4, and obtains a deviation ΔZ/δy corresponding to the Yposition of the Z grid using Z2 and Z4. Further, while main controller20 obtains a deviation ΔY/δx corresponding to the X position of the Ygrid using Y1 and Y2, in this operation, the position of fine movementstage WFS in the θz direction is calculated using X1 and X3. By thisoperation, a ΔY map and a ΔZ map as is shown in FIGS. 12A and 12B,respectively, can be obtained.

Concurrently with the position measurement of fine movement stage WFS indirections of six degrees of freedom described above, main controller20, at a predetermined sampling interval, repeatedly performs thedifference measurement described above, and performs an update of griderrors of the coordinate system of the first back side encoder system70A. Hereinafter, this update of grid errors will be called, refreshingthe coordinate system of the first back side encoder system 70A.

Accordingly, in the present embodiment, by using the first back sideencoder system 70A, main controller 20 can constantly performmeasurement of position information of fine movement stage WFS withinthe XY-plane directly below the exposure position (the rear surface sideof fine movement stage WFS) when transferring the pattern of reticle Ronto a plurality of shot areas of wafer W mounted on fine movement stageWFS.

In this case, with heads 73 a to 73 d described above, because theoptical paths of the measurement beams in the air are extremely shortand are substantially equal, the influence of air fluctuation can bepractically ignored. Accordingly, position information of fine movementstage WFS in directions of six degrees of freedom can be measured withhigh precision by the first back side encoder system 70A. Further,because the substantial detection points on the grating in the X-axis,the Y-axis, and the Z-axis directions according to the first back sideencoder system 70A each coincide with the center (exposure position) ofexposure area IA, generation of the so-called Abbe error can besuppressed to a level that can be practically ignored. Accordingly, byusing the first back side encoder system 70A, main controller 20 canmeasure the position of fine movement stage WFS in the X-axis direction,the Y-axis direction, and the Z-axis direction with high precision,without any Abbe errors. Incidentally, while the first back side encodersystem 70A can be made only to measure position information indirections of six degrees of freedom of wafer table WTB (or wafer stageWST), the first back side encoder system 70A can preferably be made tomeasure position information of wafer table WTB (or wafer stage WST)using at least another measurement beam other than the plurality ofmeasurement beams necessary for measurement of position information indirections of six degrees of freedom, as in the present embodiment.

Next, a structure and the like of the first top side encoder system 80Astructuring a part of the first fine movement stage position measurementsystem 110A will be described. The first top side encoder system 80A canmeasure position information of fine movement stage WFS in directions ofsix degrees of freedom concurrently with the first back side encodersystem 70A.

In exposure apparatus 100, as shown in FIG. 4, a pair of head sections62A and 62C are placed on the +X side and the −X side of projection unitPU (nozzle unit 32), respectively. Head sections 62A and 62C to bedescribed later on, each include a plurality of heads, and these headsare fixed to main frame BD (not shown in FIG. 4, refer to FIG. 1 and thelike) in a suspended state, via a support member.

Head sections 62A and 62C, as shown in FIG. 4, are equipped withfour-spindle heads 65 ₁ to 65 ₄ and four-spindle heads 64 ₁ to 64 ₄,each having four heads. Inside the respective housings of four-spindleheads 65 ₁ to 65 ₄, as shown in FIG. 5, XZ heads 65X₁ to 65X₄ whosemeasurement directions are in the X-axis and the Z-axis directions, andYZ heads 65Y₁ to 65Y₄ whose measurement directions are in the Y-axis andthe Z-axis directions are housed. Similarly, inside the respectivehousings of four-spindle heads 64 ₁ to 64 ₄, XZ heads 64X₁ to 64X₄ andYZ heads 64Y₁ to 64Y₄ are housed. As each of the XZ heads 65X₁ to 65X₄and 64X₁ to 64X₄, and YZ heads 65Y₁ to 65Y₄ and 64Y₁ to 64Y₄, an encoderhead having a structure similar to the displacement measurement sensorhead disclosed in, for example, U.S. Pat. No. 7,561,280, can be used.

XZ heads 65X₁ to 65X₄ and 64X₁ to 64X₄ (to be more precise, irradiationpoints on scales 39 ₁ and 39 ₂ of the measurement beams generated by XZheads 65X₁ to 65X₄ and 64X₁ to 64X₄) are placed on a straight line(hereinafter called a reference axis) LH which passes through opticalaxis AX (in the present embodiment, also coinciding with the center ofexposure area IA previously described) of projection optical system PLand is also parallel to the X-axis, at a predetermined interval WD.Further, YZ heads 65Y₁ to 65Y₄ and 64Y₁ to 64Y₄ (to be more precise,irradiation points on scales 39 ₁ and 39 ₂ of the measurement beamsgenerated by YZ heads 65Y₁ to 65Y₄ and 64Y₁ to 64Y₄) are placed on astraight line LH which is parallel to reference axis LH and is also apredetermined distance away from reference axis LH to the −Y side, atthe same X positions corresponding to XZ heads 65X₁ to 65X₄ and 64X₁ to64X₄. Hereinafter, XZ heads 65X₁ to 65X₄ and 64X₁ to 64X₄, and YZ heads65Y₁ to 65Y₄ and 64Y₁ to 64Y₄ will also be expressed as XZ heads 65X and64X, and YZ heads 65Y and 64Y, respectively, as necessary. Incidentally,reference axis LH coincides with straight line LX1 previously described.

Head sections 62A and 62C use scales 39 ₁ and 39 ₂, respectively, tostructure a multiple-lens (four-lens in this case) XZ linear encoderwhich measures the position in the X-axis direction (X position) and theposition in the Z-axis direction (Z position) of wafer table WTB, and tostructure a multiple-lens (four-lens in this case) YZ linear encoderwhich measures the position in the Y-axis direction (Y position) and theZ position. Hereinafter, for the sake of convenience, these encoderswill be expressed as XZ linear encoders 65X and 64X, and YZ linearencoders 65Y and 64Y (refer to FIG. 17), using the same reference signsas XZ heads 65X and 64X, and YZ heads 65Y and 64Y, respectively.

In the present embodiment, XZ linear encoder 65X and YZ linear encoder65Y structure (refer to FIG. 17) a multiple-lens (four-lens in thiscase) four-spindle encoder 65 which measures position informationrelated to each of the X-axis, the Y-axis, the Z-axis, and the θxdirections of wafer table WTB. Similarly, XZ linear encoder 64X and YZlinear encoder 64Y structure (refer to FIG. 17) a multiple-lens(four-lens in this case) four-spindle encoder 64 which measures positioninformation related to each of the X-axis, the Y-axis, the Z-axis, andthe θx directions of wafer table WTB.

Here, interval WD in the X-axis direction of the four XZ heads 65X and64X (to be more precise, irradiation points on scales 39 ₁ and 39 ₂ ofthe measurement beams generated by XZ heads 65X and 64X) and the four YZheads 65Y and 64Y (to be more precise, irradiation points on the scalesof the measurement beams generated by YZ heads 65Y and 64Y) that headsections 62A and 62C are equipped with, respectively, is set narrowerthan the width of scales 39 ₁ and 39 ₂ in the X-axis direction.Accordingly, on exposure and the like, at least one head each of each ofthe four XZ heads 65X and 64X and YZ heads 65Y and 64Y constantly faces(irradiates the measurement beam on) the corresponding scales 39 ₁ and39 ₂. Here, the width of the scale refers to the width of thediffraction grating (or the area formed), or to be more precise, a rangewhere position measurement using the head is possible.

Accordingly, four-spindle encoder 65 and four-spindle encoder 64structure the first top side encoder system 80A which measures positioninformation in directions of six degrees of freedom of fine movementstage WFS supported by coarse movement stage WCS, in the case waferstage WST is at exposure station 200.

Measurement values of each encoder structuring the first top sideencoder system 80A are supplied to main controller 20, via switchingsection 150A (refer to FIGS. 16, 17 and the like).

Further, although it is omitted in the drawings, when main controller 20drives wafer stage WST in the X-axis direction, main controller 20sequentially switches XZ heads 65X and 64X and YZ heads 65Y and 64Ywhich measure position information of wafer table WTB to adjacent XZheads 65X and 64X and YZ heads 65Y and 64Y. That is, in order tosmoothly perform this switching (joint) of such XZ heads and YZ heads,as previously described, interval WD of adjacent XZ heads and YZ headsincluded in head sections 62A and 62C is set smaller than the width ofscales 39 ₁ and 39 ₂ in the X-axis direction.

As it can be seen from the description so far, in the presentembodiment, in the case wafer stage WST is located at exposure station200, position information in directions of six degrees of freedom offine movement stage WFS supported by coarse movement stage WCS can bemeasured concurrently using the first back side encoder system 70A andthe first top side encoder system 80A.

However, the first top side encoder system 80A and the first back sideencoder system 70A each have the following merits and demerits.

While the first top side encoder system 80A has a demerit of having adisadvantage in frequency characteristic because a variation in a staticcomponent (including a component in an extremely low frequency band) ofthe measurement signal is large due to a long-term variation such asdeformation of plate 28 and drift and the like of heads 65X, 64X, 65Y,and 64Y, and a place of wafer table WTB having a low rigidity and alarge amplitude is observed, on the contrary, influence by vibration ofthe body is small, and the encoder system has a merit of keepingmeasurement deception small except for the extremely low frequency band.

Meanwhile, while the first back side encoder system 70A has a merit ofhaving an advantage in frequency characteristic because there is littlelong-term variation such as deformation of grating RG and drift and thelike of heads 73 a to 73 d, reliability in a static component of themeasurement signal is high and also a high rigidity portion of finemovement stage WFS is observed in the high frequency band, becausemeasurement arm 71A (arm member 71 ₁) is structured supported in acantilevered state and the length of the arm is 500 mm or more, theencoder system has a demerit of being significantly influenced by abackground vibration (vibration of body) in a band of around 100 Hz to400 Hz.

Therefore, in the present embodiment, when wafer stage WST is positionedat exposure station 200 including the time of exposure to be describedlater on, as shown in FIG. 13A, for example, the first back side encodersystem 70A and the first top side encoder system 80A concurrentlyperform measurement of position information of fine movement stage WFS(wafer table WTB), so that position control of wafer table WTB isperformed based on the position information having higher reliability.Therefore, the first back side encoder system 70A and the first top sideencoder system 80A are connected to main controller 20 via switchingsection 150A (refer to FIGS. 16, 17 and the like).

FIG. 18 shows an example of a concrete structure of switching section150A. Switching section 150A is equipped with two selector switchsections 158 a and 158 b, and a hybrid filter section 160 where anoutput signal F_(B) of the first back side encoder system 70A is inputvia one output terminal a of selector switch section 158 a and an outputsignal F_(T) of the first top side encoder system 80A is input via oneoutput terminal d of selector switch section 158 b, and a hybridposition signal F_(H) is output to main controller 20.

Selector switch section 158 a has an input terminal (not shown)connected to the first back side encoder system 70A and three outputterminals a, b, and c, and performs switching and connecting between theinput terminal and one of the three output terminals a, b, and c. Inthis case, output terminal b is connected to main controller 20, andoutput terminal c is a terminal which is not connected anywhere(hereinafter referred to as an open terminal).

Selector switch section 158 b has an input terminal (not shown)connected to the first top side encoder system 80A and three outputterminals d, e, and f, and performs switching and connecting between theinput terminal and one of the three output terminals d, e, and f. Inthis case, output terminal e is connected to main controller 20, andoutput terminal f is an open terminal.

The switching in selector switch sections 158 a and 158 b is performedby the input of a switching signal (or a selecting signal) shown by abroken line in FIG. 18 from main controller 20. Main controller 20inputs the switching signal (or the selecting signal) to selector switchsections 158 a and 158 b, according to a predetermined processingalgorithm, or from instructions from the outside.

In the present embodiment, switching section 150A is selectively set tothe following four states by main controller 20.

Switching section 150A is set to a first state where the input terminalof selector switch section 158 a is connected to output terminal a, andthe input terminal of selector switch section 158 b is connected tooutput terminal d, respectively. In this first state, as it will bedescribed later on, switching section 150A outputs hybrid positionsignal F_(H) to main controller 20.

Switching section 150A is set to a second state where the input terminalof selector switch section 158 a is connected to output terminal b, andthe input terminal of selector switch section 158 b is connected tooutput terminal e, respectively. In this second state, switching section150A outputs output signal F_(B) of the first back side encoder system70A, and output signal F_(T) of the first top side encoder system 80A tomain controller 20.

Switching section 150A is set to a third state where the input terminalof selector switch section 158 a is connected to output terminal b, andthe input terminal of selector switch section 158 b is connected to anopen terminal f, respectively. In this third state, switching section150A outputs only output signal F_(B) of the first back side encodersystem 70A to main controller 20.

Switching section 150A is set to a fourth state where the input terminalof selector switch section 158 a is connected to open terminal c, andthe input terminal of selector switch section 158 b is connected tooutput terminal e, respectively. In this fourth state, switching section150A outputs only output signal F_(T) of the first top side encodersystem 80A to main controller 20.

Hereinafter, for the sake of convenience, the first, the second, thethird, and the fourth states will be called the first, the second, thethird, and the fourth modes of switching section 150A. That is,switching section 150A is a mode setting section which selectively setsthe four modes of the output to main controller 20.

When switching section 150A is set to the first mode described above,with output signal F_(B) of the first back side encoder system 70A andoutput signal F_(T) of the first top side encoder system 80A serving asthe inputs, hybrid filter section 160 outputs hybrid position signalF_(H) used for position control of fine movement stage WFS to maincontroller 20.

Hybrid filter section 160 is equipped with a first filter section 160 a,which has a low pass filter Lfc₁ whose cutoff frequency is fc₁ and ahigh pass filter Hfc₂ whose cutoff frequency is fc₂ (>fc₁) to whichoutput signal F_(B) of the first back side encoder system 70A is input,and outputs an addition signal of signals that have passed through eachof the two filters Lfc₁ and Hfc₂, and a second filter section 160 b,which has a high pass filter Hfc₁ whose cutoff frequency is fc₁ and alow pass filter Lfc₂ whose cutoff frequency is fc₂ to which outputsignal F_(T) of the first top side encoder system 80A is input, andoutputs an addition signal of signals that have passed through each ofthe two filters Hfc₁ and Lfc₂. Hybrid filter section 160 outputs anaddition signal of the output of the first filter section 160 a and theoutput of the second filter section 160 b as hybrid position signalF_(H), to main controller 20.

Here, cutoff, frequency fc₁ is set, for example, to a frequency slightlylower than the lower limit frequency 100 Hz of a frequency band 100 Hzto 400 Hz of the background vibration which affects the first back sideencoder system 70A, such as, for example, to 50 Hz. Further, cutofffrequency fc₂ is set, for example, to a frequency slightly higher thanthe upper limit frequency 400 Hz of the frequency band 100 Hz to 400 Hzof the background vibration which affects the first back side encodersystem 70A, such as, for example, to 500 Hz.

In the case of setting the cutoff frequencies fc₁ and fc₂ in the mannerdescribed above, from hybrid filter section 160, as shown by a solidline in FIG. 13B, in the low-frequency area lower than 50 Hz, the outputsignal (measurement results of the position) of the first back sideencoder system 70A, in a midfrequency band higher than 50 Hz and lowerthan 500 Hz, the output signal (measurement results of the position) ofthe first top side encoder system 80A, and in a high-frequency areahigher than 500 Hz, the output signal (measurement results of theposition) of the first back side encoder system 70A, are each output ashybrid position signal F_(H).

By such setting, in the low-frequency area where reliability ofmeasurement values decreases due to the first top side encoder system80A being affected by plate deformation and head drift, measurementvalues of the first back side encoder system 70A which is not affectedby such issues and has high reliability, in the midfrequency area wherereliability of measurement values decreases due to the first back sideencoder system 70A being affected by background vibration, measurementvalues of the first top side encoder system 80A which is hardly affectedby such vibration and has high reliability, and in a high-frequency areawhere there is a demerit in frequency characteristic because the firsttop side encoder system 80A observes a place of wafer table WTB whoserigidity is low and amplitude is high, measurement values of the firstback side encoder system 70A having an advantage in frequencycharacteristic, are each output to main controller 20 as measurementresults of a position of wafer table WTB within the XY-plane.Accordingly, main controller can drive (control the position of) finemovement stage WFS when wafer stage WST is at exposure station 200,constantly based on position measurement values of wafer table WTBhaving high reliability.

As is described, in the present embodiment, when switching section 150Ais set to the first mode, position control of wafer table WTB isperformed by switching the measurement information (measurement signal)of the first back side encoder system 70A and the first top side encodersystem 80A depending on the frequency band, so that as a consequence,position control is performed based on the measurement information witha higher reliability. Incidentally, for example, in the case the firsttop side encoder system 80A does not cause a disadvantage in frequencycharacteristic in the high-frequency area, cutoff frequency fc₂ does nothave to be set. In this case, only a filter circuit section has to beprovided which synthesizes a hybrid position signal of the outputsignals of the first back side encoder system 70A and the first top sideencoder system 80A, using the high pass filter and the low pass filterof cutoff frequency fc₁.

Further, switching section 150A is set, for example, to the third modeor to the fourth mode in the case when reliability of the measurementinformation of the first back side encoder system 70A is obviouslyhigher, or in the case when reliability of the measurement informationof the first top side encoder system 80A is higher.

Further, switching section 150A is set to the second mode in the casewhen both of the measurement information of the first back side encodersystem 70A and the measurement information of the first top side encodersystem 80A have to be taken in.

Meanwhile, as described above, in the present embodiment, when switchingsection 150A is set to the first mode, because drive (position control)of fine movement stage WFS is performed based on the measurement valuesof the first top side encoder system 80A in the midfrequency area, it ispreferable that an update of a coordinate system set by atwo-dimensional grating of the pair of scales 39 ₁ and 39 ₂ beperformed, that is, an update (hereinafter called refreshing thecoordinate system of the first top side encoder system 80A) of the grid(grid error) of the pair of scales 39 ₁ and 39 ₂ be performed.

Therefore, when wafer stage WST is at exposure station 200 such as, forexample, during exposure, main controller 20 performs refreshing thecoordinate system of the first top side encoder system 80A in the mannerdescribed below.

The relation between the coordinate system of the first back sideencoder system 70A and the plurality of four-spindle heads 65 ₁ to 65 ₄and 64 ₁ to 64 ₄ of the first top side encoder system 80A in the presentembodiment can be expressed as shown in FIG. 14A. Here, R₁, R₂, R₃, andR₄ are equivalent to four-spindle heads 65 ₁, 65 ₂, 65 ₃, and 65 ₄,respectively, and L₁, L₂, L₃, and L₄ are equivalent to four-spindleheads 64 ₁, 64 ₂, 64 ₃, and 64 ₄, respectively.

Reference sign Ct_(i)(i=1, 2, 3, 4) denotes the coordinate system of thefirst back side encoder system 70A suspended by L_(i) and R_(i), thatis, denotes a partial coordinate system corresponding to an area ontwo-dimensional grating RG observed by three-dimensional encoder 73 adirectly below the exposure position of the first back side encodersystem 70A when R_(i) and L_(i) observe scales 39 ₁ and 39 ₂,respectively. The distance from the center of a whole coordinate systemof the first back side encoder system 70A to R₁, R₂, R₃, and R₄ isexpressed as D₁, D₂, D₃, and D₄, respectively, and whenD_(i)+D_((5-i))=W, then grid distortion Δi (x_(i),y_(i)) of Ct_(i) canbe expressed as in formula (1) below. Here, Δ is a three-dimensionalvector that has x, y, and z components.

Δ_(i)(x _(i) ,y _(i))=1/W·{D _(i) ΔL(x _(i) ,y _(i))+D _((5-i))Δ_(R)(x_(i) ,y _(i))}  (1)

When (x_(i),y_(i)) in formula (1) is generalized and deformed to (x,y),the following formula (1)′ can be obtained.

WΔ _(i)(x,y)=D _(i)Δ_(L)(x,y)+D _((5-i))Δ_(R)(x,y)  (1)′

When substituting 1, 2, 3, 4 into i of formula (1)′, the followingformulas (2) to (5) can be obtained.

WΔ ₁(x,y)=D ₁Δ_(L)(x,y)+D ₄Δ_(R)(x,y)  (2)

WΔ ₂(x,y)=D ₂Δ_(L)(x,y)+D ₃Δ_(R)(x,y)  (3)

WΔ ₃(x,y)=D ₃Δ_(L)(x,y)+D ₂Δ_(R)(x,y)  (4)

WΔ ₄(x,y)=D ₄Δ_(L)(x,y)+D ₁Δ_(R)(x,y)  (5)

From the sum and difference of formulas (2) and (5), two formulas areobtained, and by solving the two formulas, the following two formulascan be obtained.

Δ_(L)(x,y)=WΔ ₁(x,y)/D ₁

Δ_(R)(x,y)=WΔ ₄(x,y)/D ₄

Similarly, from the sum and difference of formulas (3) and (4), twoformulas are obtained, and by solving the two formulas, the followingtwo formulas can be obtained.

Δ_(L)(x,y)=WΔ ₂(x,y)/D ₂

Δ_(R)(x,y)=WΔ ₃(x,y)/D ₃

Accordingly, it can be seen that from grid distortion Δ_(i)(x_(i),y_(i))of Ct_(i), grid distortion Δ_(L)(t,s), Δ_(R)(t,s) of scales 39 ₂ and 39₁ as shown in FIG. 14B can be obtained.

Main controller 20 obtains and updates grid distortion Δ_(L)(t,s),Δ_(R)(t,s) of scales 39 ₂ and 39 ₁ according to the principle describedabove at least once, for example, during exposure of each wafer at apredetermined interval. That is, by comparing and adjusting the grid ofthe scale of the first top side encoder system 80A to the coordinatesystem of the first back side encoder system 70A whose grid has beenupdated, the grid is updated. That is, refreshing the coordinate systemof the first top side encoder system 80A is performed in the mannerdescribed above.

However, on refreshing the coordinate system of the first top sideencoder system 80A, main controller 20 does not perform the comparingand adjusting and the update described above regarding offset of thecoordinate system in directions of six degrees of freedom (in each ofthe X-axis, the Y-axis, the Z-axis, the θx, the θy and the θzdirections), and stores the information without any changes. The reasonfor this is because the coordinate system of back side encoder system70A does not have long-term stability in directions of six degrees offreedom, and the top side encoder system 80A coordinate system is morereliable, due to reasons such as measurement arm 71A lacking inmechanical long-term stability, and further, for example, the intervalbetween the detection points of the plurality of heads used for positionmeasurement in the θx, θy, and θz directions is small. Accordingly, therefreshing processing described above is performed after removing theoffset in directions of six degrees of freedom described above from theback/top difference. The offset component in the six degrees of freedomdescribed above will be used in a post stream processing which will bedescribed later on.

Next, a structure of the second fine movement stage position measurementsystem 110B (refer to FIG. 16) used for measuring position informationof fine movement stage WFS, which is movably held by coarse movementstage WCS located at measurement station 300, will be described.

The second back side encoder system 70B of the second fine movementstage position measurement system 110B is equipped with measurement arm71B (refer to FIG. 1) which is inserted within a space provided insidecoarse movement stage WCS, in a state where wafer stage WST is placedbelow alignment device 99 (alignment systems AL1, and AL2 ₁ to AL2 ₄).

Measurement arm 71B, as shown in FIG. 9A, has an arm member 71 ₂ whichis supported by main frame BD via support member 72B in a cantileveredstate, and an encoder head (optical system) which will be describedlater on housed inside arm member 71 ₂. In measurement arm 71B, whilethe length of arm member 71 ₂ is longer than arm member 71 ₁ previouslydescribed, as a whole, measurement arm 71B is structured roughlysymmetrical to measurement arm 71A previously described.

As previously described, in the state where wafer stage WST is placedbelow alignment device 99 (alignment systems AL1, and AL2 ₁ to AL2 ₄),as shown in FIG. 9A, the tip of arm member 71 ₂ of measurement arm 71Bis inserted into the space of coarse movement stage WCS, and its uppersurface faces grating RG (not shown in FIGS. 1 and 7, refer to FIG. 2Band the like) provided on the lower surface of fine movement stage WFS(wafer table WTB) (to be more precise, the lower surface of main section81). The upper surface of arm member 71 ₂ is placed almost parallel tothe fine movement stage WFS lower surface, in a state where apredetermined clearance gap (clearance, gap), such as for example, a gapor around several mm, is formed with the lower surface of fine movementstage WFS.

The second back side encoder system 708, as shown in FIG. 17, includes apair of three-dimensional encoders 75 a and 75 b which each measures theposition of fine movement stage WFS in the X-axis, the Y-axis, and theZ-axis directions, an XZ encoder 75 c which measures a position of finemovement stage WFS in the X-axis and the Z-axis directions, and a YZencoder 75 d which measures a position of fine movement stage WFS in theY-axis and the Z-axis directions, similar to the first back side encodersystem 70A previously described.

XZ encoder 75 c and YZ encoder 75 d are equipped, respectively, with atwo-dimensional head whose measurement direction is in the X-axis andthe Z-axis direction, and a two-dimensional head whose measurementdirection is in the Y-axis and the Z-axis direction, housed respectivelyinside of arm member 71 ₂. Hereinafter, for the sake of convenience, thetwo-dimensional heads that XZ encoder 75 c and YZ encoder 75 d each areequipped with will be expressed as XZ head 75 c and YZ head 75 d, usingthe same reference signs as each of the encoders. Three-dimensionalencoders 75 a and 75 b are equipped with a three-dimensional head whosemeasurement direction is in the X-axis, Y-axis, and Z-axis directions.Hereinafter, for the sake of convenience, the three-dimensional headsthat three-dimensional encoders 75 a and 75 b each are equipped withwill be expressed as three-dimensional heads 75 a and 75 b, using thesame reference signs as each of the encoders. As two-dimensional heads75 c and 75 d, and three-dimensional heads 75 a and 75 b, heads having astructure similar to two-dimensional heads 73 c and 73 d, andthree-dimensional heads 73 a and 73 b previously described can be used.

FIG. 9B shows a perspective view of the tip of measurement arm 71B. Asshown in FIG. 9B, three-dimensional heads 75 a and 75 b, andtwo-dimensional heads 75 c and 75 d are placed in a symmetrical butsimilar positional relation to three-dimensional heads 73 a and 73 b,and two-dimensional heads 73 c and 73 d previously described, inside ofarm member 71 ₂. The detection center of one of three-dimensional heads75 a coincides with the alignment position, that is, with the detectioncenter of primary alignment system AL1.

The output of encoders 73 a and 73 b, and 73 c and 73 d of the secondback side encoder system 70B is supplied to main controller 20 viaswitching section 150B (refer to FIGS. 16, 17 and the like), which isstructured similarly to switching section 150A previously described.

When wafer stage WST is positioned at measurement station 300, such asfor example, at the time of wafer alignment which will be describedlater on, main controller 20 performs refreshing the coordinate systemof the second back side encoder system by repeatedly performing positionmeasurement of wafer table WTB in directions of six degrees of freedomas is previously described while concurrently performing differencemeasurement as is previously described at a predetermined samplinginterval, based on measurement values of a total of ten degrees offreedom by heads 75 a to 75 d of the second back side encoder system70B. The preceding description can be applied without any changes to theposition measurement and difference measurement in this case, if theexposure position previously described is replaced to alignmentposition.

Incidentally, in the present embodiment, because the detection point ofthree-dimensional head 75 a coincides with the alignment position, andthe position of fine movement stage WFS in the X-axis, the Y-axis, andthe Z-axis directions is measured at the detection point, the positionof fine movement stage WFS in the X-axis, the Y-axis, and the Z-axisdirections is calculated using the measurement values ofthree-dimensional head 75 a. Different from this, such as for example,in the case the alignment position coincides with a point in the centerof the detection points of a pair of three-dimensional heads 75 a and 75b, main controller 20 can obtain the position of fine movement stage WFSin the X-axis, the Y-axis, and the Z-axis directions, based on anaverage value of the measurement values of the pair of three-dimensionalheads 75 a and 75 b in each of the X-axis, the Y-axis, and the Z-axisdirections.

Further, because the substantial detection points on grating RG in theX-axis, Y-axis and Z-axis directions by the second back side encodersystem 70B each coincide with the detection center (alignment position)of primary alignment system AL1, generation of the so-called Abbe erroris suppressed to a level which can be substantially ignored.Accordingly, by using the second back side encoder system 70B, maincontroller 20 can measure the position of fine movement stage WFS in theX-axis direction, the Y-axis direction, and the Z-axis directions withhigh precision, without the Abbe error.

Next, a structure and the like of the second top side encoder system 80Bstructuring a part of the second fine movement stage positionmeasurement system 110B will be described. The second top side encodersystem 80B can measure position information of fine movement stage WFSin directions of six degrees of freedom concurrently with the secondback side encoder system 70B.

In exposure apparatus 100, as shown in FIG. 4, on the −Y side of each ofthe head sections 62C and 62A and almost at the same Y position asalignment systems AL1, and AL2 ₁ to AL2 ₄, head sections 62E and 62F areplaced, respectively. Head sections 62E and 62F, as described later on,each include a plurality of heads, and these heads are fixed to mainframe BD in a suspended state via a support member.

Head sections 62F and 62E, as shown in FIG. 4, are equipped with foureach of four-spindle heads 68 ₁ to 68 ₄, and 67 ₁ to 67 ₄. Inside therespective housings of four-spindle heads 68 ₁ to 68 ₄, as shown in FIG.5, similar to four-spindle heads 65 ₁ to 65 ₄ and the like previouslydescribed, XZ heads 68X₁ to 68X₄ and YZ heads 68Y₁ to 68Y₃ are housed.Similarly, inside the respective housings of four-spindle heads 67 ₁ to67 ₄, XZ heads 67X₁ to 67X₄ and YZ heads 67Y₁ to 67Y₄ are housed. Aseach of the XZ heads 68X₁ to 68X₄ and 67X₁ to 67X₄, and YZ heads 68Y₁ to68Y₃ and 67Y₁ to 67Y₄, an encoder head having a structure similar to thedisplacement measurement sensor head disclosed in, for example, U.S.Pat. No. 7,561,280 can be used.

XZ heads 67X₁ to 67X₃ and 68X₂ to 68X₄ (to be more precise, irradiationpoints on scales 39 ₁ and 39 ₂ of the measurement beams generated by XZheads 67X₁ to 67X₃ and 68X₂ to 68X₄) are placed along reference axis LApreviously described, at almost the same X position as XZ heads 64X₁ to64X₃ and 65X₂ to 65X₄, respectively.

YZ heads 67Y₁ to 67Y₃ and 68Y₂ to 68Y₄ (to be more precise, irradiationpoints on scales 39 ₁ and 39 ₂ of the measurement beams generated by YZheads 67Y₁ to 67Y₃ and 68Y₂ to 68Y₄) are placed on a straight line LA₁which is parallel to reference axis LA and is distanced to the −Y sidefrom reference axis LA, at almost the same X position as thecorresponding XZ heads 67X₁ to 67X₃ and 68X₂ to 68X₄.

Further, the remaining XZ heads 67X₄ and 68X₁ and YZ heads 67Y₄ and 68Y₁are placed at almost the same X position as each of the XZ heads 64X₄and 65X₁ on the −Y side of the detection center of each of the secondaryalignment systems AL2 ₁ and AL2 ₄, shifted to the −Y direction by thesame distance from reference axis LA and straight line LA. Hereinafter,as necessary, XZ heads 68X₁ to 68X₄ and 67X₁ to 67X₄, and YZ heads 68Y₁to 68Y₄ and 67Y₁ to 67Y₄ will each be expressed also as XZ heads 68X and67X, and YZ heads 68Y and 67Y.

Head sections 62F and 62E use scales 39 ₁ and 39 ₂, respectively, andstructure a multiple-lens (four-lens in this case) XZ linear encoderwhich measures the X position and Z position of wafer table WTB, and amultiple-lens (four-lens in this case) YZ linear encoder which measuresthe Y position and Z position. Hereinafter, for the sake of convenience,these encoders will be expressed as XZ linear encoders 68X and 67X andYZ linear encoders 68Y and 67Y (refer to FIG. 17), using the samereference signs as XZ heads 68X and 67X, and YZ heads 68Y and 67Y,respectively.

In the present embodiment, XZ linear encoder 68X and YZ linear encoder68Y structure (refer to FIG. 17) a multiple-lens (four-lens in thiscase) four-spindle encoder 68 which measures position information ofwafer table WTB related to each direction in the X-axis, the Y-axis, theZ-axis and θx directions. Similarly, XZ linear encoder 67X and YZ linearencoder 67Y structure (refer to FIG. 17) a multiple-lens (four-lens inthis case) four-spindle encoder 67 which measures position informationof wafer table WTB related to each direction in the X-axis, the Y-axis,the Z-axis and the θx directions.

Here, for the similar reasons as is previously described, on alignmentmeasurement and the like, at least one head each of the four XZ heads68X and 67X and YZ heads 68Y and 67Y constantly faces (irradiates ameasurement beam on) the corresponding scales 39 ₁ and 39 ₂.Accordingly, four-spindle encoder 68 and four-spindle encoder 67structure the second top side encoder system 80B which measures positioninformation in directions of six degrees of freedom of fine movementstage WFS supported by coarse movement stage WCS, in the case waferstage WST is at measurement station 300.

Measurement values of each encoder structuring the second top sideencoder system 80B are supplied to main controller 20 via switchingsection 150B (refer to FIGS. 16, 17 and the like). As is obvious fromthe description so far, in the present embodiment, in the case waferstage WST is at measurement station 300, position information indirections of six degrees of freedom of fine movement stage WFSsupported by coarse movement stage WCS can be measured concurrently bythe second back side encoder system 70B and the second top side encodersystem 80B.

Further, switching section 150B has a first mode to a fourth mode set bymain controller 20, similar to switching section 150A. And, in the casethe first, the third, or the fourth mode is set, according to the modesetting, hybrid filter section 160 supplies measurement values of ahigher reliability to main controller 20 from measurement values of thesecond back side encoder system 70B and the second top side encodersystem 80B, and drive (position control) of wafer table WTB is to beperformed based on the supplied measurement values when wafer stage WSTis at measurement station 300.

Further, main controller 20, as is previously described, performsrefreshing the coordinate system of the second top side encoder system80B by comparing and adjusting the grid of the scale of the second topside encoder system 80B to the coordinate system of the second back sideencoder system 70B whose grid has been updated.

Incidentally, for the second back side encoder system 70B and the secondtop side encoder system 80B of the second fine movement stage positionmeasurement system 110B, besides the description so far, the descriptionearlier concerning the first back side encoder system 70A and the firsttop side encoder system 80A can also be applied without any changes.

Now, although the description falls out of sequence, the third back sideencoder system 70C (refer to FIG. 16) will be described which is used atthe time of focus mapping to be described later on, when necessary, onmeasuring the position of fine movement stage WFS (wafer table WTB) ineach of the Y-axis, the Z-axis, the θy, and the θz directions.

In arm member 71 ₂ of measurement arm 71B, as shown in FIG. 9B, a pairof YZ heads 77 a and 77 b is placed further inside of arm member 71 ₂,so that points set apart by the same distance to the +Y side from thedetection centers of three-dimensional heads 75 a and 75 b respectivelyserve as detection centers of the pair of YZ heads. The detection centerof YZ head 77 a on the +X side coincides with an AF center, or in otherwords, the detection center of the multi-point AF system (90 a, 90 b)previously described. This pair of YZ heads 77 a and 77 b structures thethird back side encoder system 70C.

The output of the third back side encoder system 70C is supplied to maincontroller 20, via switching section 150C (refer to FIGS. 16, 17 and thelike) structured in a similar manner as switching section 150Apreviously described. When the output of the third back side encodersystem 70C is supplied to main controller 20 via switching section 150C,main controller 20 obtains a Y position and Z position of fine movementstage WFS (wafer table WTB) based on position information in the Y-axisand the Z-axis directions measured by YZ head 77 a, and obtains aposition in the θz direction (θz rotation) and a position in the θydirection (θy rotation) of fine movement stage WFS (wafer table WTB),based on position information in the Y-axis direction and the Z-axisdirection measured by the pair of YZ heads 77 a and 77 b.

Incidentally, in the case the alignment center coincides with the centerof detection points of the pair of three-dimensional heads 75 a and 75b, the AF center is set so as to coincide with the center of thedetection points of the pair of YZ heads 77 a and 77 b. Accordingly, inthis case, main controller 20 obtains the Y position and Z position offine movement stage WFS (wafer table WTB) from an average value ofposition information in the Y-axis and the Z-axis directions measured bythe pair of YZ heads 77 a and 77 b.

Incidentally, for the third back side encoder system 70C, although thereis some difference in position and number of the heads, besides thedescription so far, the description made earlier on the first back sideencoder system 70A can be basically applied.

In the present embodiment, corresponding to the third back side encodersystem 70C, the third top side encoder system 80C is also provided(refer to FIG. 16). The third top side encoder system 80C, as shown inFIG. 4, includes a pair of four-spindle heads 66 ₁ and 66 ₂ placedsymmetrical to reference axis LV. The pair of four-spindle heads 66 ₁and 66 ₂ are placed at a position to the +Y side of four-spindle head 68₃ and a position to the +Y side of four-spindle head 67 ₂, respectively,and are fixed to main frame BD in a suspended state via a supportmember. The pair of four-spindle heads 66 ₁ and 66 ₂, as shown in FIG.5, include XZ heads 66X₁ and 66X₂ and YZ heads 66Y₁ and 66Y₂,respectively, with each of the detection points placed along the Y-axisdirection, similar to the four-spindle heads 64 _(i), 65 _(i), 67 _(i),and 68 _(i) previously described. The Y position of the detection pointsof XZ heads 66X₁ and 66X₂ that the pair of four-spindle heads 66 ₁ and66 ₂ have, respectively, coincides with the Y position (on straight lineLA₂) of the detection center of the AF beam. Further, the X position ofthe detection point of XZ head 66X₂ is positioned slightly to the +Xside of the detection point of XZ head 67X₂, and the X position of thedetection point of XZ head 66X₁ is positioned slightly to the −X side ofthe detection point of XZ head 68X₃. The pair of four-spindle heads 66 ₁and 66 ₂ structures a pair of four-spindle encoders which measuresposition information of wafer table WTB in each of the X-axis, theY-axis, the Z-axis, and the θx directions, using scales 39 ₁ and 39 ₂,respectively. This pair of four-spindle encoders structures the thirdtop side encoder system 80C.

Measurement values of each encoder structuring the third top sideencoder system 80C are supplied to main controller 20, via switchingsection 150C (refer to FIGS. 16, 17 and the like) which is structuredsimilar to switching section 150A.

In the present embodiment, by the third top side encoder system 80C andthe third back side encoder system 70C, position information related todirections in four degrees of freedom (each of the Y-axis, the Z-axis,the θz and the θy directions) of wafer table WTB (fine movement stageWFS) can be measured concurrently.

Further, switching section 150C has a first mode to a fourth mode set bymain controller 20, similar to switching section 150A. And, in the casethe first, the third, or the fourth mode is set, according to the modesetting, hybrid filter section 160 supplies measurement values of ahigher reliability to main controller 20 from measurement values of thethird back side encoder system 70C and the third top side encoder system80C.

However, at the time of focus mapping which will be described later on,wafer stage WST is at measurement station 300 and wafer alignmentmeasurement is performed concurrently with the focus mapping, and untilthis alignment measurement is completed, main controller 20 performsservo control on the position in directions of six degrees of freedom offine movement stage WFS (wafer table WTB), based on the hybrid positionsignal previously described of the second fine movement stage positionmeasurement system 110B, and the measurement values of the third topside encoder system 80C and the third back side encoder system 70C aremainly used as measurement data on focus mapping. And, after waferalignment measurement has been completed, until wafer table movesoutside of the measurement range of the second fine movement stageposition measurement system 100B and the focus mapping is completed,main controller 20 performs the drive (servo control of the position) offine movement stage WFS based on the measurement values of the third topside encoder system 80C and/or the third back side encoder system 70C.

In the present embodiment, furthermore, when wafer stage WST moves froma finishing position of focus mapping to exposure station 200, thefourth top side encoder system 80D is provided (refer to FIG. 16) so asto measure the position in directions of six degrees of freedom of wafertable WTB during this movement. The fourth top side encoder system 80D,as shown in FIG. 4, includes a pair of three-dimensional heads 79 ₁ and79 ₂ which are placed at a position halfway between head section 62A andhead section 62F in the Y-axis direction, shifted to the X-axisdirection and the Y-axis direction. The pair of three-dimensional heads79 ₁ and 79 ₂ is fixed to main frame BD in a suspended state via asupport member. The pair of three-dimensional heads 79 ₁ and 79 ₂, asshown in FIG. 5, includes XZ heads 79X₁ and 79X₂ and Y heads 79Y₁ and79Y₂, respectively, which are placed lined in the Y-axis direction. Yheads 79Y₁ and 79Y₂ are one-dimensional heads whose measurementdirection is in the Y-axis direction. In this case, the X positions ofXZ heads 79X₁ and 79X₂ are set to the same positions as XZ heads 68X₂and 66X₁, respectively. As each of the Y heads 79Y₁ and 79Y₂, adiffractive interference type encoder head such as the one disclosed in,for example, U.S. Patent Application Publication No. 2008/0088843 andthe like, can be used.

The pair of three-dimensional heads 79 ₁ and 79 ₂ structures a pair ofthree-dimensional encoders 79A and 79B (refer to FIG. 16) which measuresposition information in the X-axis, the Y-axis, and the Z-axisdirections of wafer table WTB, both using scale 39 ₁. Measurement valuesof this pair of three-dimensional encoders 79A and 79B are supplied tomain controller 20. The pair of three-dimensional heads 79 ₁ and 79 ₂can measure the position in directions of six degrees of freedom ofwafer table WTB using the same scale 39 ₁ when the center position ofwafer table WTB in the X-axis direction coincides with reference axisLV. The pair of three-dimensional encoders 79A and 79B structures thefourth top side encoder system 80D.

Incidentally, for the fourth top side encoder system 800D, althoughthere is some difference in position and number of the heads, besidesthe description so far, the description made earlier on the first backside encoder system 80A can be basically applied.

In exposure apparatus 100 of the present embodiment, as shown in FIG. 4,an unloading position UP1 is set at a predetermined position between theexposure position and the alignment position on reference axis LV, forexample, at almost the same Y position as XZ head 79X₁ ofthree-dimensional head 79 ₁ on reference axis LV, and at a position apredetermined distance away to the −X side from unloading position UP1,a standby position UP2 is set. Further, on the −Y side of the alignmentposition on reference axis LV, a loading position LP is set.

At unloading position UP1, standby position UP2, and the area nearby, asshown in FIG. 15, an unloading device 170 is placed. Unloading device170 is placed vibrationally separated from main frame BD in theperiphery of main frame BD, such as for example, attached to a frame FLwhich has a rectangular frame shape in a planar view, supported on thefloor surface by a support member not shown.

Unloading device 170 is equipped with a first arm 171 which is fixed tothe lower surface (a surface on the −Z side) of frame FL and extends,for example, in a direction forming a predetermined angle α (α is apredetermined angle, for example, smaller than 10 degrees) with respectto the Y-axis, a second arm 172 which extends in the X-axis directionwhose edge surface on one end in the longitudinal direction is fixed toa side surface (+X side surface) on one end (+Y side end) in thelongitudinal direction of the first arm 171, a first unloading slider170A which is movable along the longitudinal direction of the second arm172, and a second unloading slider 170B which is movable along thelongitudinal direction of the first arm 171.

The first arm 171 consists of a rod-shaped member which is placed facingthe lower surface of frame FL, in a state where one end in thelongitudinal direction faces a side section of frame FL on the −X sideclose to the center in the Y-axis direction, and the other end in thelongitudinal direction faces the side section of frame FL on the −X sideat the end on the −Y side. The first arm 171 has its entire uppersurface or a plurality of places of the upper surface fixed to the lowersurface of frame FL. To the lower surface (rear surface) of the firstarm 171, a guide which is not shown is provided along the longitudinaldirection, and a stator which is not shown is placed parallel to theguide.

The second arm 172 consists of a rod-shaped member having almost thesame length as the first arm 171. The second arm 172 is fixed on a sidesurface (+X side surface) on one end (+Y side end) in the longitudinaldirection of the first arm 171, in a state where an angle of (90degrees—α) is formed within the XY-plane with respect to the first arm172. To the lower surface (rear surface) of the second arm 172, similarto the first arm 171, a guide which is not shown is provided along thelongitudinal direction, and a stator which is not shown is placedparallel to the guide.

The first unloading slider 170A is equipped with a first slide member173 provided movable along the guide described above on the rear surfaceof the second arm 172, and a wafer grasping member 174 having an X shapein a planar view that is placed below the first slide member 173 and ismoved vertically by a vertical movement drive section 176 provided inthe first slide member 173 (refer to, for example, FIG. 36A). In thefirst slide member 173, a mover is incorporated that structures a linearmotor for driving the first slider along with the stator described aboveplaced in the second arm 172.

Wafer grasping member 174, as shown in FIG. 15, is equipped with a mainsection 174 a consisting of a pair of rod-shaped members which iscombined in an X shape in a planar view, and four grasping members 174 beach attached to the four tips of main section 174 a.

The size of the pair of rod-shaped members in the longitudinal directionstructuring main section 174 a is slightly longer than the diameter ofwafer W, and the pair of rod-shaped members is placed so that the rodsintersect at a predetermined angle in the center of the longitudinaldirection. With main section 174 a, the intersecting part of the pair ofrod-shaped members is fixed to the lower surface of a drive shaft ofvertical movement drive section 176.

Here, with the pair of rod-shaped members of main section 174 a, becausethe four grasping members 174 b only has to grasp wafer W on wafer stageWST, a groove can be formed in the center on the upper surface (or thelower surface) of one of the rod-shaped members, and by inserting theother rod-shaped member into the groove, both rods can be fixed so thatthe height of the upper surface (or the lower surface) of each of therod-shaped members becomes the same, or the lower surface of one of therod-shaped members can be fixed to the other rod-shaped member. In thecase of connecting the pair of rod-shaped members at a position wherethe height of the pair of rod-shaped members is different (for example,in the case when the other rod-shaped member is fixed to the lowersurface of one of the rod-shaped members), it is preferable to match theZ-axis direction position of the lower end of the four grasping members174 b, such as by adjusting the length in the Z-axis direction ofgrasping members 174 b provided in both ends of one of the rod-shapedmembers, or by using a member having a shape projecting upward (orprojecting downward) so that both ends of one of the rod-shaped membersare adjusted to have the same height as both ends of the otherrod-shaped member.

Each of the four grasping members 174 b has a claw section provided atthe lower end that can support the rear surface of the wafer. Each ofthe four grasping members 174 b can be moved and slid along therod-shaped member to which each of the members are attached via a drivemechanism which is not shown. That is, the four grasping members 174 bcan be opened or closed (refer to FIG. 36C).

In the present embodiment, a first unloading slider driving system 180A(refer to FIG. 16) is structured including the linear motor for drivingthe first slider previously described, vertical movement drive section176, and the drive mechanism described above for opening and closing thegrasping member 174 b.

The second unloading slider 170B is equipped with a second slide member175 which is provided movable along the guide described above on therear surface of the first arm 171, and a Y shape holding section 177which is placed below the second slide member 175 and is verticallymoved and rotationally driven around the Z-axis by a vertical movementrotation driving section 179 provided in the second slide member 175(for example, refer to FIG. 32A). In the second slide member 175, amover is incorporated which structures a linear motor for driving thesecond slider along with the stator described above placed on the firstarm 171.

Y shape holding section 177, as shown in FIG. 15, consists of a thinplate member having a Y shape in a planar view, and has on its uppersurface a suction section which is not shown where wafer W is held bysuction by vacuum chucking (or electrostatic suction). The size in theXY-plane of Y shape holding section 177 is slightly smaller than waferW, and in a state where wafer W is held above the suction section, thetip (that is, a tip-split section) of the Y shape fits the outerperiphery of wafer W. The end on the opposite side of the Y shape tip ofY shape holding section 177 is fixed to the lower end of the drive shaftof vertical movement rotation driving section 179.

In the present embodiment, a second unloading slider driving system 180B(refer to FIG. 16) is structured including the linear motor for drivingthe second slider previously described, and vertical movement rotationdriving section 179.

The first unloading slider driving system 180A and the second unloadingslider driving system 180B are controlled by main controller 20 (referto FIG. 16). Incidentally, the unloading device is not limited to thestructure described above, and may be of any structure as long as it ismovable holding wafer W. Further, the unloading position of wafer W isalso not limited to the position between projection optical system PLand alignment device 99, and for example, unloading can be performed onthe opposite side of projection optical system PL with respect toalignment device 99 as in the second embodiment to be described lateron.

FIG. 16 is a block diagram showing an input/output relation of maincontroller 20 which mainly structures a control system of exposureapparatus 100 and has overall control over each structuring parts. Maincontroller 20 includes a workstation (or a microcomputer) and the like,and has overall control over each of the sections that structureexposure apparatus 100. FIG. 17 shows an example of a concrete structureof the first and the second fine movement stage position measurementsystems 110A and 110 in FIG. 16. Further, FIG. 18 shows an example of astructure of switching section 150A in FIG. 16.

Next, a concurrent processing operation using wafer stage WST andmeasurement stage MST in exposure apparatus 100 related to the presentembodiment will be described, based on FIGS. 19 to 37. Incidentally, inthe following operation, main controller 20 performs control of liquidsupply device and liquid recovery device 6 of local liquid immersiondevice 8 as is previously described, and water is constantly filled inthe space below tip lens 191 of projection optical system PL. However,in the description below, for a straightforward description, descriptionon the control related to liquid supply device 5 and liquid recoverydevice 6 will be omitted. Further, while a number of drawings will beused in the description on the operation hereinafter, the same membermay or may not have a reference sign applied in each of the drawings.That is, although the reference sign written for each of the drawingsmay be different, these drawings show the same structure, regardless ofthe availability of reference signs. The same is said for each of thedrawings used in the description so far. Further, in the drawingsfollowing FIG. 19, measurement stage MST is briefly illustrated.

Further, in the case when each head of the first to the third back sideencoder systems 70A to 70C and the first to the fourth top side encodersystems 80A to 80D, the multi-point AF system, the alignment systems andthe like are used, or a little before their usage, while their state isset from an off state to an on state, the description regarding thispoint will be omitted when describing the operation hereinafter.

Further, as a premise, switching sections 150A and 150B, as an example,are both to be set to the first mode, and switching section 150C is, forexample, to be set to the second mode. More specifically, from the firstfine movement stage position measurement system 110A, measurement values(hereinafter, except for cases when it is especially necessary, thevalues will be referred to as measurement values of the first finemovement stage position measurement system 110A) corresponding to hybridposition signal F_(H) of the first back side encoder system 70A and thefirst top side encoder system 80A, and from the second fine movementstage position measurement system 110B, measurement values (hereinafter,except for cases when it is especially necessary, the values will bereferred to as measurement values of the second fine movement stageposition measurement system 110B) corresponding to hybrid positionsignal F_(H) of the second back side encoder system 70B and the firsttop side encoder system 80B, are output to main controller 20. Further,from the third back side encoder system 70C and the third top sideencoder system 80C, the output signals (measurement values) are eachoutput to main controller 20.

FIG. 19 shows a state where wafer stage WST is at loading position LP,and measurement stage MST is directly below projection optical systemPL. At this point, measurement arm 71B is inserted into the space ofwafer stage WST, and the rear surface (grating RG) of wafer table WTBfaces measurement arm 71B. At this loading position LP, a new wafer W(here, as an example, the wafer is to be a wafer in the middle of a lot(1 lot including 25 or 50 slices of wafers)) which has not yet undergoneexposure is loaded on wafer stage WST in the order described below.

At this point, after a stream processing to be described later on to thepreceding wafer has been completed, wafer W which has not yet beenexposed is already supported by chuck unit 120 previously described atloading position LP at the point before exposure begins, and thissupport state is maintained. To be concrete, as shown in FIG. 20A, waferW is suctioned (held or supported) in a non-contact manner whilemaintaining a predetermined distance (gap) by Bernoulli chuck 124 whichis at a predetermined height position at loading position LP, and twoplaces at the outer circumference of its rear surface are supported in acontact manner from below by the pair of support plates 128, whichlimits the movement in directions of six degrees of freedom. Further,the temperature of wafer W is controlled by cool plate 123 to apredetermined temperature, for example, to 23° C.

Main controller 20, first of all, as shown in FIG. 20B, drives the threevertical movement pins 140 previously described upward, via driver 142.And, when the three vertical movement pins 140 come into contact withthe rear surface of wafer W supported by Bernoulli chuck 124, the upwarddrive of vertical movement pins 140 is stopped, while maintaining thecontact state. When the upper end surface of the three vertical movementpins 140 is at a position other than the second position serving as alowest end position of the upper end surface within the moving range,vertical movement pins 140 are pressed by a constant force in the +Zdirection by springs not shown.

Next, main controller 20 drives the pair of support plates 128 slightlydownward via the pair of vertical movement rotation driving sections 127and separates the pair of support plates 128 from the rear surface ofwafer W, and rotates the pair of support plates 128 at a predeterminedangle as shown in FIG. 20C so as to position the pair of support plates128 at the second rotating position. By the separation from the rearsurface of wafer W of the pair of support plates 128 described above,the new wafer W has moved from a state where the wafer is supported bysupport plates 128 to a state where the wafer is supported by verticalmovement pins 140. Incidentally, Bernoulli chuck 124 continues thesuction (hold or support) of wafer W in this state as well, and by thesuction (hold or support) of wafer W by Bernoulli chuck 124 and thefrictional force due to the support from below of vertical movement pins140, movement of wafer W is limited in directions of six degrees offreedom. Further, the temperature control of wafer W by cool plate 123is also being continued.

Next, main controller 20, as shown in FIG. 20D, controls drive section122 and the pair of vertical movement rotation driving sections 127, anddrives chuck main section 130 and the pair of support plates 128downward. In this case, the upward force to the three vertical movementpins 140 by the force of the springs previously described is applied towafer W as prepressure. Accordingly, by chuck main section 130 beingdriven downward, wafer W is pushed downward, and pushes the threevertical movement pins 140 downward resisting the prepressure. That is,in the manner described above, wafer W is driven downward along withchuck main section 130 and the three vertical movement pins 140, whilemaintaining a predetermined gap with respect to Bernoulli chuck 124.And, when the rear surface of wafer W comes into contact with the waferholder (wafer table WTB), main controller 20 releases the suction (holdor support) of wafer W by Bernoulli chuck 124, and makes the waferholder hold wafer W by suction. This allows wafer W to be held by thewafer holder with the bending which occurs substantially suppressed orprevented. That is, Bernoulli chuck 124 is equipped with not only thecarrier function, and the temperature control function and pre-alignmentfunction previously described, but also with a bending correcting(correction) function. Because the wafer W held by the wafer holder isflattened, this bending correction function can also be called aflattening function. Incidentally, while wafer W held by Bernoulli chuck124 is maintained substantially flat without any bending, for example,by Bernoulli chuck 124 delivering wafer W to the wafer holder in a statewhere bending is generated in at least a part of wafer W which is held,as a consequence, the bending of wafer W held by the wafer holder can besuppressed or prevented. Further, a detection device (for example, thegap sensor and the like previously described) for detecting positioninformation in the Z direction or bending information of the wholesurface or a part of the surface of wafer W held by Bernoulli chuck 124can be provided, and main controller can use such detection results tomaintain wafer W held by Bernoulli chuck 124 flat without bending, orwith a bending generated in at least a part of the wafer by Bernoullichuck 124. Furthermore, while suction release of wafer W by Bernoullichuck 124 can be performed before suction of wafer W by the wafer holderbegins, for example, for correction (flattening) of the bending of waferW, the suction release can be performed simultaneously with thebeginning of suction of wafer W by the wafer holder or after thebeginning of suction. Further, main controller 20 can begin suction holdof wafer W by the wafer holder, simultaneously, with releasing thesupport of wafer W by the three vertical movement pins 140, or can beginthe suction hold of wafer W by the wafer holder prior to releasing thesupport of wafer W by the three vertical movement pins 140.

Here, prior to releasing the suction (hold or support) of wafer WhyBernoulli chuck 124, main controller 20 can apply a downward force fromabove by chuck main section 130 to a part of or to the whole wafer Wwhose rear surface (lower surface) is pushed (in contact) to the waferholder (wafer table WTB). Here, the downward force refers to a forceother than gravity. As a method of applying this downward force, forexample, increasing the flow volume and/or flow velocity of the gasblowing out from Bernoulli chuck 124, or narrowing the gap (clearance)between the lower surface of Bernoulli chuck 124 and the surface ofwafer W from the predetermined gap at the time of driving chuck mainsection 130 downward, can be considered. In any case, wafer W is held bysuction by the wafer holder after the downward force is applied, orwhile the downward force is being applied. This substantially suppressesor prevents the bending from occurring in wafer W held by the waferholder.

Further, main controller 20 can control the suction state by the waferholder so that suction holding of wafer W by the wafer holder isperformed with a time lag, for example, begins with a time lag from theperiphery section toward the center, or begins from one side to itsopposite side with a time lag. Especially in the latter case, the waferholder (wafer table WTB) can be tilted in the θx direction and/or the θydirection. By performing such suction hold of wafer W by the waferholder combined with the bending correction of wafer W by Bernoullichuck 124, wafer W is held by the wafer holder with the bendingsubstantially suppressed or prevented.

In the present embodiment, while chuck main section 130 and the threevertical movement pins 140 are driven downward in the manner describedabove, imaging signals of imaging device 129 are sent to signalprocessing system 116 (refer to FIG. 16), and information on positionaldeviation and rotation errors of wafer W is supplied to main controller20 (refer to FIG. 16). Incidentally, three vertical movement pins 140can be driven downward synchronously with Bernoulli chuck 124 (chuckmain section 130), or, the three vertical movement pins 140 can bedriven downward without being in synchronization. Especially in thelatter case, main controller 20 can make the lowering speed of the threevertical movement pins 140 and the lowering speed of chuck main section130 different so as to flatten wafer W. In this case, for example, thegap sensor previously described can be placed at a plurality of placesof Bernoulli chuck 124, and main controller 20 can detect the deformedstate of wafer W using the plurality of gap sensors (for example,whether the protrusion is to the upper side or the protrusion is to thelower side and the like), and the lowering speed of the three verticalmovement pins 140 and the lowering speed of chuck main section 130 canbe made different, according to the detection results.

In the present embodiment, as it can be seen from FIG. 20A, because astate where vertical movement pins 140 have been driven upward by apredetermined amount is maintained at the point when wafer table WTBreturns to loading position LP, wafer loading can be performed in ashort time than when vertical movement pins 140 are housed inside of thewafer holder. FIG. 19 shows a state where wafer W is loaded on wafertable WTB.

In the present embodiment, as shown in FIG. 19, loading position LP isset to a position where fiducial mark FM on measurement plate 30 ispositioned within the field (detection area) of primary alignment systemAL1 (in other words, a position where the first half processing of baseline measurement (Pri-BCHK) of primary alignment system AL1 isperformed).

Here, the first half processing of Pri-BCHK refers to the processingdescribed hereinafter. That is, main controller 20 detects (observes)fiducial mark FM located in the center of measurement plate 30previously described with primary alignment system AL1, makes thedetection results of primary alignment system AL1 correspond with themeasurement values of fine movement stage position measurement system110B at the time of detection, and stores the information in memory.

In the present embodiment, the first half processing of Pri-BCHK isperformed concurrently with at least a part of the loading operation ofwafer W.

At this point, measurement stage MST engages with measurement arm 71A ina state where the rear surface (grating RGa) of measurement table MTBfaces measurement arm 71A. Further, a liquid immersion area 14 by liquidLq is formed between measurement table MTB and projection optical systemPL.

Further, at this point, a wafer (refer to as W₀) that has already beenexposed, is held by Y shape holding section 177 of the second unloadingslider 170B at a predetermined height position of standby position UL2.This waiting state of wafer W₀ is maintained until exposure of the nextwafer W begins and wafer stage WST reaches a state where it withdrawsfrom below standby position UL2.

Next, main controller 20 drives coarse movement stage WCS based onmeasurement values of wafer stage position measurement system 16A, andbegins a moving operation in the +Y direction of wafer stage WST fromloading position LP toward exposure station 200 while performing servocontrol on the position of wafer table WTB based on the measurementvalues of the second fine movement stage position measurement system110B. This movement of wafer stage WST in the +Y direction, first ofall, for example, begins with moving toward a position where alignmentmarks arranged in three first alignment shot areas (hereinafter shortlyreferred to as a first alignment mark) are detected. At this point,servo control is performed on the position of wafer table WTB indirections of six degrees of freedom, based on the measurement values ofthe second fine movement stage position measurement system 110B.Incidentally, while coarse movement stage WCS is driven within theXY-plane based on the position information measured by wafer stageposition measurement system 16A in exposure station 200, measurementstation 300, or in any areas in between, hereinafter, the descriptionregarding this point will be omitted.

Then, during the movement toward the +Y direction, when wafer stage WSTreaches the position shown in FIG. 21, that is, a position where adetection beam from light transmitting system 90 a is irradiated onmeasurement plate 30, main controller 20 stops wafer stage WST, andbegins to perform the first half processing of focus calibration.

That is, while main controller 20 detects surface position information(Z position information of scales 39 ₁ and 39 ₂) at the end on one sideand the other side in the X-axis direction of wafer table WTB detectedby the pair of XZ heads 66X₁ and 66X₂ of the third top side encodersystem 80C previously described, with a reference plane obtained fromsuch information serving as a reference, main controller 20 detectssurface position information of the surface of measurement plate 30previously described, using the multi-point AF system (90 a, 90 b). Fromthis detection, a relation is obtained between measurement values (thesurface position information at the end on one side and the other sidein the X-axis direction of wafer table WTB) of the pair of XZ heads 66X₁and 66X₂ in a state where the center line of wafer table WTB coincideswith reference axis LV previously described, and the detection results(surface position information) at a detection point (a detection pointlocated at the center or near the center among a plurality of detectionpoints) on the surface of measurement plate 30 of the multi-point AFsystem (90 a, 90 b).

Further, in the present embodiment, because the position of wafer tableWTB where the first half processing of focus calibration described aboveis performed coincides with the position of wafer table WTB whereprocessing of detecting the three first alignment marks is performed,main controller 20 detects the three first alignment marks (refer to thestar marks in FIG. 21) almost simultaneously and individually usingprimary alignment system AL1, and secondary alignment systems AL2 ₂ andAL2 ₃, concurrently with the first half processing of focus calibration,and then associates the detection results of the three alignment systemsAL1, AL2 ₂, and AL2 ₃ described above with the measurement values of thesecond fine movement stage position measurement system 110B at the timeof detection, and stores the information in memory which is not shown.Incidentally, the simultaneous detection of the three first alignmentmarks in this case is performed by varying the Z position of wafer tableWTB, while changing the relative positional relation in the Z-axisdirection (focus direction) between the plurality of alignment systemsAL1, AL2 ₁ to AL2 ₄, and wafer W mounted on wafer table WTB. Thedetection of alignment marks arranged in each alignment shot area fromthe second and subsequent alignment shot areas described below is alsoperformed in a similar manner.

Incidentally, in the case the position of wafer table WTB where thefirst half processing of focus calibration is performed does notcoincide with the position of wafer table WTB where processing of thedetection of the first alignment mark is performed, main controller 20can sequentially perform these processing according to the order inwhich wafer table WTB reaches the position where each of the processingis performed.

Next, main controller 20 begins movement (for example, step movementtoward a position where alignment marks arranged in five secondalignment shot areas (hereinafter shortly referred to as secondalignment marks) are detected) of wafer stage WST in the +Y direction.

Then, when wafer stage WST moves further in the +Y direction, andreaches the position shown in FIG. 22, main controller 20 detects thefive second alignment marks almost simultaneously and individually usingthe five alignment systems A1, and AL2 ₁ to AL2 ₄ (refer to the starmarks in FIG. 22), and then associates the detection results of the fivealignment systems AL1, and AL2 ₁ to AL2 ₄ described above with themeasurement values of the second fine movement stage positionmeasurement system 110B at the time of detection, and stores theinformation in memory which is not shown.

Further, in the present embodiment, as shown in FIG. 22, at thisposition to detect the second alignment marks, the detection beam fromlight transmitting system 90 a begins to hit wafer W. And then, afterthe detection of the second alignment marks, main controller 20 beginsfocus mapping, using the four-spindle heads 66 ₁ and 66 ₂ of the thirdtop side encoder system 80C and the multi-point AF system (90 a, 90 b).

Now, focus mapping performed in exposure apparatus 100 related to thepresent embodiment will be described. On this focus mapping, maincontroller 20, as shown in FIG. 22, for example, controls the positionof wafer table WTB within the XY-plane, based on the measurement valuesof the two four-spindle heads 66 ₁ and 66 ₂ of the third top sideencoder system 80C that face scales 39 ₁ and 39 ₂, respectively. In thisstate shown in FIG. 22, a straight line (center line) parallel to theY-axis which passes through the center of wafer table WTB (substantiallycoincides with the center of wafer W) coincides with reference axis LV.

And, in this state, while wafer stage WST is proceeding toward the +Ydirection, main controller 20 takes in position information related tothe Y-axis and the Z-axis directions of both ends (the pair of thesecond water repellent plates 28 b) in the X-axis direction of wafertable WTB surface (plate 28 surface) measured by each of the twofour-spindle heads 66 ₁ and 66 ₂, and position information (surfaceposition information) related to the Z-axis direction of the wafer Wsurface at the plurality of detection points detected by the multi-pointAF system (90 a, 90 b) at a predetermined sampling interval, makes theposition information related to the Y-axis and the Z-axis directions andthe position information related to the Z-axis direction that have beentaken in correspond to each other, and then stores the information inmemory which is not shown.

Then, when the detection beam of the multi-point AF system (90 a, 90 b)moves off wafer W, main controller 20 completes the sampling describedabove, and converts the surface position information for each detectionpoint of the multi-point AF system (90 a, 90 b) into data, which uses asa reference the position information related to the Z-axis directionmeasured by each of the two four-spindle heads 66 ₁ and 66 ₂ that hasbeen taken in simultaneously.

To describe this further in detail, surface position information at apredetermined point (corresponding to a point on substantially the sameX-axis as the arrangement of the plurality of detection points of themulti-point AF system (90 a, 90 b): hereinafter, referring to this pointas a left measurement point) on an area (the second water repellentplate 28 b on which scale 39 ₂ is formed) near the −X side edge of plate28 is obtained, based on measurement values of the Z position of one ofthe four-spindle heads 66 ₂. Further, surface position information at apredetermined point (corresponding to a point on substantially the sameX-axis as the arrangement of the plurality of detection points of themulti-point AF system (90 a, 90 b): hereinafter, referring to this pointas a right measurement point) on an area (the second water repellentplate 28 b on which scale 39 ₁ is formed) near the +X side edge of plate28 is obtained, based on measurement values of the Z position of theother four-spindle head 66 ₁. Then, main controller 20 converts thesurface position information at each detection point of the multi-pointAF system (90 a, 90 b) to surface position data which uses a straightline formed by connecting the surface position of the left measurementpoint and the surface position of the right measurement point(hereinafter referred to as a table surface reference line) as areference. Main controller 20 performs such a conversion on all of theinformation taken in at the time of sampling.

Here, in exposure apparatus 100 related to the present embodiment,concurrently with the measurement by the third top side encoder system80C described above, measurement of position information of wafer tableWTB (fine movement stage WFS) in the Y-axis direction, the Z-axisdirection, and the θy direction (and the θz direction) is possible bythe third back side encoder system 70C. Therefore, at the same timing astaking in position information related to the Y-axis and the Z-axisdirections on both ends in the X-axis direction of the wafer table WTBsurface (surface of plate 28) measured by each of the two four-spindleheads 66 ₁ and 66 ₂ described above, and position information (surfaceposition information) related to the Z-axis direction of the wafer Wsurface at a plurality of detection points detected by the multi-pointAF system (90 a, 90 b), main controller 20 also takes in measurementvalues related to position in each of the directions (Y, Z, and θy (andθz)) described above measured by the third back side encoder system 70C.Then, main controller 20 obtains a relation between the data (Z, θy) oftable surface reference line obtained from the measurement informationof the third top side encoder system 80C and the measurement information(Z, θy) of the third back side encoder system 70 which weresimultaneously taken in. This allows the surface position data describedabove which uses the table surface reference line as a reference to beconverted to surface position data which uses a reference line(hereinafter called a rear surface measurement reference line for thesake of convenience) that corresponds to the table surface referenceline described above and is decided by the Z position and By rotation ofwafer table WTB obtained by the rear surface measurement.

By acquiring the conversion data described above in advance in themanner described above, for example, on exposure and the like, the wafertable WTB surface (a point on the second water repellent plate 28 b onwhich scale 39 ₂ is formed, and a point on the second water repellentplate 28 b on which scale 39 ₁ is formed) is measured with XZ heads 64Xand 65X previously described, and the Z position and tilt (mainly θyrotation) with respect to the XY-plane of wafer table WTB arecalculated. By using the Z position and the tilt with respect to theXY-plane of wafer table WTB which have been calculated and the surfaceposition data (surface position data which uses the table surfacereference line as a reference) previously described, it becomes possibleto perform surface position control of wafer W, without actuallyobtaining the surface position information of the wafer W surface.Accordingly, because there are no problems when the multi-point AFsystem is placed at a position distanced from projection optical systemPL, focus mapping of the present embodiment can be suitably applied evenwhen the working distance (spacing between projection optical system PLξ wafer W at the time of exposure) of the exposure apparatus is small.

The description so far is based on a premise that there is no unevennesson the wafer table WTB surface. However, actually, the surface of wafertable WTB, namely the surface of the second water repellent plate 28 bon which scale 39 ₂ is formed, the surface of the second water repellentplate 28 b on which scale 39 ₁ is formed and the like, are uneven.However, even if the surface of wafer table WTB is uneven as such, atpoints on a meridian of wafer W (a straight line passing through thewafer center parallel to the Y-axis), surface position control ispossible at an extremely high precision.

The reason for this is because the shot area positioned on the meridianof wafer W when focus mapping is performed (while wafer stage WST ismoving in the +Y direction) on exposure and the like is to be placed atthe exposure position (below projection optical system PL), withoutwafer stage WST (wafer table WTB) being moved in the X-axis directionwhen compared with the time of focus mapping. When the shot area on themeridian reaches the exposure position, XZ head 65X₃ whose detectionpoint is placed at substantially the same X position as XZ head 66X₁ andXZ head 64X₂ whose detection point is placed at substantially the same Xposition as XZ head 66X₂ are to detect surface position information atsubstantially the same point as the point on wafer table WTB whosesurface position information was detected by each of XZ head 66X₁ and XZhead 66X₂ at the time of focus mapping. That is, a reference surface (asurface formed by continuously joining the table surface reference linein the Y-axis direction) measured by the pair of XZ heads, serving as areference when detecting surface position information by the multi-pointAF system (90 a, 90 b) becomes the same at the time of focus mapping andat the time of exposure. Therefore, even if the surface of wafer tableWTB is uneven or has waviness, when the shot area on the meridian isexposed, because focus control of the wafer at the time of exposure canbe performed without taking into consideration the unevenness andwaviness, using the Z position obtained at the time of focus mapping asthe Z position without any changes, focus control with high precisioncan be performed.

Similarly, when the shot area on the meridian reaches the exposureposition, three-dimensional head 73 a whose detection point is set onthe same straight line (reference axis LV) parallel to the Y-axis as thedetection point of YZ head 77 a, and three-dimensional head 73 b whosedetection point is set on the same straight line parallel to the Y-axisas the detection point of YZ head 77 b are to detect the Z position atthe same point as a point on grating RG where the YZ head and the YZhead each detected the surface position information at the time of focusmapping, and based on the detection results, calculation of Z and θy isto be performed. That is, a surface formed by continuously joining therear surface measurement reference line previously described in theY-axis direction (hereinafter referred to as a rear surface measurementreference surface), which serves as a reference when detecting surfaceposition information using the multi-point AF system (90 a, 90 b), is tobe calculated, based on a measurement value of the Z position at thesame point at the time of focus mapping and exposure.

When exposing a shot area other than the shot area on the meridian, inthe case there are no unevenness and waviness on the surface of wafertable WTB, while focus control accuracy of around the same level as inthe exposure of the shot area on the meridian described above can besecured, in the case there are unevenness, waviness, and the like on thesurface of wafer table WTB, the focus control accuracy depends on theaccuracy of a traverse checking which will be described later on.

Incidentally, in the present embodiment, because the detection beam fromlight transmitting system 90 a begins to hit wafer W when wafer stageWST reaches the position for detecting the second alignment marks, focusmapping was made also to start at the position. However, in the case thedetection beam from light transmitting system 90 a begins to hit wafer Wprior to, or after wafer stage WST has reached the position fordetecting the second alignment marks, focus mapping can be started priorto, or after detecting the second alignment mark, at the point when thedetection beam begins to hit wafer W.

The description now returns to describing the concurrent operation. Whenwafer stage WST moves in the +Y direction for the focus mappingdescribed above, and reaches the position shown in FIG. 23, maincontroller 20 stops wafer stage WST at the position. Then, for example,using the five alignment systems AL1, and AL2 ₁ to AL2 ₄, maincontroller 20 detects alignment marks arranged in five third alignmentshot areas (hereinafter shortly referred to as third alignment marks)(refer to the star marks in FIG. 23) almost simultaneously andindividually, associates the detection results of the five alignmentsystems AL1, and AL2 ₁ to AL2 ₄ described above with the measurementvalues of the second fine movement stage position measurement system110B at the time of detection, and stores the information in memorywhich is not shown. Further, focus mapping is still being continued atthis point.

Next, main controller 20, for example, begins to move wafer stage WST inthe +Y direction, toward a position for detecting alignment marksprovided in three fourth alignment shot areas (hereinafter shortlyreferred to as fourth alignment marks). At this point, focus mapping isbeing continued.

Then, when wafer stage WST reaches the position shown in FIG. 24, maincontroller 20 immediately stops wafer stage WST, detects the threefourth alignment marks (refer to the star marks in FIG. 24) on wafer Walmost simultaneously and individually, using primary alignment systemAL1, and secondary alignment systems AL2 ₂ and AL2 ₃, and associates thedetection results of the three alignment systems AL1, AL2 ₂, and AL2 ₃above with the measurement values of the second fine movement stageposition measurement system 1108 at the time of detection, and storesthe information in memory which is not shown.

Then, main controller 20 performs a statistical calculation based on anEGA method disclosed in, for example, U.S. Pat. No. 4,780,617, using thedetection results of a total of 16 alignment marks obtained in themanner described above and the corresponding measurement values of thesecond fine movement stage position measurement system 110B, andcalculates an EGA parameter (X offset, Y offset, orthogonal degree,wafer rotation, wafer X scaling, wafer Y scaling and the like).

After wafer alignment (processing until position measurement of at leastthe fourth alignment marks) described above has been completed, maincontroller 20 moves wafer stage WST to a position shown in FIG. 27, thatis, to a starting position of a state where wafer stage WST andmeasurement stage MST are in contact, or for example, are approachingeach other with a separation distance of around 300 μm in between(hereinafter, referred to as an in contact or an approaching state) inthe Y-axis direction. This movement is performed by main controller 20moving wafer stage WST at a high speed with long strokes at once in the+Y direction, in a state where wafer table WTB does not come intocontact with the liquid. Further, during this movement, because waferstage WST moves away from the measurement range of the second finemovement stage position measurement system 110B, prior to this, maincontroller 20 switches the measurement system used for servo control ofthe position of wafer table WTB from the second fine movement stageposition measurement system 110B to the fourth top side encoder system80D.

Immediately after wafer stage WST begins to be moved at a high speedwith long strokes in the +Y direction as described above, maincontroller 20 continues focus mapping. Then, when the detection beamfrom the multi-point AF system (90 a, 90 b) moves away from the wafer Wsurface, main controller 20 completes focus mapping, as shown in FIG.25.

During the processing (hereinafter referred to as a stream processing)described above in which alignment measurement and focus mapping areperformed while wafer stage WST is moved in a straight line in the +Ydirection, in a manner similar to refreshing the coordinate system ofthe first back side encoder system 70A and refreshing the coordinatesystem of the first top side encoder system 80A previously described,main controller 20 performs refreshing the coordinate system of thesecond back side encoder system 70B and refreshing the coordinate systemof the second top side encoder system 80B.

Now, at the time of alignment and the like, posture of wafer table WTBat measurement station 300 is controlled by the second back side encodersystem 70B. However, for the same reasons as in the first back sideencoder system 70A described earlier, long-term stability in directionsof six degrees of freedom of the coordinate system of the second backside encoder system 70B cannot be expected. However, global variation ofposition in the θy direction (rolling amount) and position in the θzdirection (yawing amount) affects results of the alignment measurement.Therefore, at the point when the stream processing has been completedduring the movement of wafer stage WST at a high speed with long strokesin the +Y direction as described above, main controller 20 begins a poststream processing which will be described below, and performs alignmentcalculation using the results of this post stream processing (computingthe array coordinates of all of the shot areas on the wafer using theEGA parameter), and correction of the rear surface measurement referencesurface included in the focus mapping results.

Here, post stream processing refers to a calculation processing in whicherror factor parameters a. to c. described below included in the EGAresults and the results of focus mapping are replaced with an offset inthe θy, θz, and X-axis direction scaling which will be described belowin d.

a. a global θy offset: position in the θy direction (θy rotation amount)of the wafer table obtained by rear surface measurement using the thirdback side encoder system 70C included in the focus mapping result

b. a global θz offset: orthogonal degree/wafer rotation included in theEGA parameter

c. a global X-axis direction scaling offset: X-axis direction scaling ofthe wafer included in the EGA parameter

d. a θy, θz and X-axis direction scaling offset computed from an averageof all data observed by the second top side encoder system 80B and thethird top side encoder system 80C during a streaming processing

Here, in X-axis direction scaling, the distance (axis interval) betweenXZ heads 67X₂ and 68X₂ or XZ heads 67X₃ and 68X₃ used for alignmentmeasurement is considered invariable, and with this as a reference, thegrating interval of scales 39 ₂ and 39 ₂ of the second top side encodersystem 80B compared and adjusted to the coordinate system of the secondback side encoder system 70B is measured by XZ heads 67X₂ and 68X₂ or67X₃ and 68X₃, and the magnification of the grating interval withrespect to the reference described above is to be the X-axis directionscaling.

By the post stream processing performed in the manner described above,as a consequence, the posture of wafer table WTB is not reset using themeasurement results of a specific point on scales 39 ₁ and 39 ₂, and anaveraged posture of wafer table WTB obtained from an average of themeasurement results of the entire surface of scales 39 ₁ and 39 ₂ is tobe used for alignment calculation (calculation of array coordinates ofall shot areas on a wafer using an EGA calculation formula whoseorthogonal degree/wafer rotation and X-axis direction scaling of thewafer of the EGA parameters have been replaced to the θz and the X-axisdirection scaling described in d. above). Results of this alignmentcalculation are more reliable than in the case of resetting the postureusing the measurement results at one specific point on scales 39 ₁ and39 ₂, due to an averaging effect.

The reasons for not performing position measurement of the θz directionand θy direction using only the top side encoder system in the streamingprocessing are described in e. to h. below.

e. When only the top side encoder is used, alignment (and focus mapping)is performed only by the top side encoder system, while exposure isperformed mainly by the back side encoder system, and the references forboth systems (although being compared and adjusted) will be completelyseparated.

f. It is considered better to use the back side encoder system also foralignment even only in the narrow strip-shaped part (a strip-shaped partof the same width as the interval in the X-axis direction of thedetection points of the three-dimensional heads 75 a and 75 b).

g. Accuracy can be expected in processing of refreshing the coordinatesystem of the back side encoder system. As a consequence, an accurategrid and a flat plane can be constantly maintained. In this case, evenin the measurement of the narrow strip-shaped part, the back sideencoder system should serve as a reference as long as the θy and θzoffsets can be removed.

h. Although the top side encoder system reflects the information of theback side encoder system, the accuracy is not complete.

Next, traverse checking will be described. First of all, an error factorunique to the stream processing which is the main factor of requiring atraverse checking will be described.

In the stream processing, as is obvious from the description above,because wafer stage WST moves on a straight line parallel to the Y-axis,position information (X,Y,Z) of the wafer table (fine movement stageWFS) at different points in the X-axis direction cannot be obtained.Accordingly, also in refreshing the coordinate system of the second backside encoder system 70B, ΔX/δx, ΔY/δx, and ΔZ/δx previously describedcannot be obtained. That is, while at the time of exposure, thecoordinate system is updated as a whole in real time by refreshing thecoordinate system of the first back side encoder system 70A previouslydescribed, and the grid error is corrected in real time in the wholecoordinate system, at the time of alignment, even if refreshing thecoordinate system of the second back side encoder system 70B isperformed, the coordinate system updated only on the straight line inthe Y-axis direction passing through the center in the X-axis directionof the wafer, and as a consequence, the grid error is corrected in realtime only on the straight line. As a consequence, an error occursbetween the alignment-time coordinate system which controls the positionof the wafer stage at the time of alignment and the exposure-timecoordinate system which controls the position of the wafer stage at thetime of exposure. That is, this is the error factor unique to the streamprocessing.

Therefore, main controller 20 performs the traverse checking describedbelow, at a frequency determined in advance (at a necessary frequency),while 25 or 50 wafers in a lot is being processed.

On the traverse checking, during the stream processing described above,when wafer stage WST reaches a position in the Y-axis direction, forexample, as shown in FIG. 28, main controller 20, while controlling theposition of wafer table WTB in directions of six degrees of freedom andstepping and driving wafer stage WST in the X-axis direction within apredetermined range (within a range where the center line of wafer tableWTB moves in the X-axis direction within a predetermined width (a widthlarger than the width of scales 39 ₁ and 39 ₂ and the distance betweenthe mutual detection areas of alignment systems AL2 ₁ and AL2 ₄) whosecenter is at reference axis LV), based on the measurement values of thesecond fine movement stage position measurement system 110B, andmeasures the same alignment mark positioned near the center of wafer Wsequentially, using the five alignment systems AL1, and AL2 ₁ to AL2 ₄.Further, during the movement of wafer stage WST in the X-axis directiondescribed above, main controller 20 simultaneously takes in measurementvalues of the pair of XZ heads 66X₁ and 66X₂ which detect the surfaceposition information of the surface area (the surface of scales 39 ₁ and39 ₂) of the pair of the second water repellent plates 28 b of wafertable WTB, and detection values of the surface position information ofwafer W by the multi-point AF system (90 a, 90 b), at a predeterminedsampling interval.

By such traverse checking, a relation between the coordinate system ofthe second fine movement stage position measurement system 110B (thecoordinate system of the second top side encoder system 80A and thecoordinate system of the second back side encoder system 70A), and themulti-point AF system (90 a, 90 b) and alignment systems AL1 and AL2 ₁to AL2 ₄ can be calibrated. Specifically, the details are shown below.

A. By moving wafer stage WST in the X-axis direction within thepredetermined range described above, position information (X,Y,Z) atdifferent points in the X-axis direction of wafer table WTB (finemovement stage WFS) can be obtained, and also in refreshing thecoordinate system of the second back side encoder system 70B, obtainingΔX/δx, ΔY/δx, and ΔZ/δx previously described becomes possible, and as aconsequence, results of refreshing the coordinate system of the secondback side encoder system 70B, and results of refreshing the coordinatesystem of the second top side encoder system 80B based on the refreshingwill have better accuracy.

B. By measuring the same alignment mark positioned near the center ofwafer W as described above, a positional relation between the detectioncenter of primary alignment system AL1 and the detection center of thesecondary alignment systems AL2 ₁ to AL2 ₄, or in other words, a baseline of the secondary alignment systems AL2 ₁ to AL2 ₄ is obtained onthe coordinate system of the second fine movement stage positionmeasurement system 110B.

C. A relation between surface position information of each detectionpoint of the multi-point AF system (90 a, 90 b) and measurement values(surface position information) of the pair of XZ heads 66X₁ and 66X₂simultaneously taken in is obtained at a different sampling timing, andfrom a plurality of relations obtained, the unevenness in the X-axisdirection of the surface of scales 39 ₁ and 39 ₂ is obtained on thecoordinate system of the second fine movement stage position measurementsystem 110B. However, in order to accurately obtain the unevenness inthe X-axis direction of the surface of scales 39 ₁ and 39 ₂, an offsetbetween sensors has to be adjusted in advance in the multi-point AFsystem (90 a, 90 b).

Then, main controller 20, at the time of exposure to be described lateron, performs positioning of wafer table WTB to the exposure positionusing the base line of the secondary alignment systems AL2 ₁ to AL2 ₄described above, along with performing focus control of wafer W whileadding the unevenness information and the like in the X-axis directionof the scale surface as a correction amount.

That is, in the present embodiment, main controller 20 corrects theposition error of wafer table WTB described above caused by the uniqueerror factor which occurs on the stream processing, by actually movingwafer stage WST in the X-axis direction, in the manner described above.

Concurrently with the post stream processing previously described, asshown in a broken line arrow in FIG. 25, an operation of carrying a nextwafer (refer to as wafer W₁) to a position under chuck unit 120previously described is performed in the order described below.

As a premise of beginning to carry in the wafer, as shown in FIG. 25,wafer stage WST on which wafer W before exposure is mounted is to be ata position (a position on the +Y side of loading position LP) which iscompletely away from loading position LP. Further, at this point, thepair of support plates 128 is at the second rotating position previouslydescribed, as shown in FIG. 26A.

First of all, main controller 20 drives a wafer carrier arm 132, andcarries the new (before exposure) wafer W₁ from an external device to aspace between a pair of drive shafts 126 below Bernoulli chuck 124located at loading position LP (refer to FIG. 26A).

Next, main controller 20 controls drive section 122 of chuck unit 120and wafer carrier arm 132, and drives (refer to outlined arrows in FIG.26A) at least one of chuck main section 130 and wafer carrier arm 132 inthe Z-axis direction so that a distance between Bernoulli chuck 124 andthe new wafer W is set to a predetermined distance, such as, forexample, to around several μm. At this point, the distance betweenBernoulli chuck 124 and the new wafer W₁ is measured by a gap sensorwhich is not shown described above.

When Bernoulli chuck 124 and the new wafer W₁ are distanced by apredetermined distance, main controller 20 adjusts the flow velocity ofair blown out from Bernoulli chuck 124 so as to maintain thepredetermined distance (gap) between Bernoulli chuck 124 and the newwafer W₁, as shown in FIG. 26(B). This allows Bernoulli chuck 124 tohold wafer W₁ by suction in a non-contact manner from above via apredetermined clearance gap (gap, clearance) of around several μm. WhenBernoulli chuck 124 holds wafer W₁ by suction, the temperature of waferW₁ is adjusted to a predetermined temperature via cool plate 123.

When wafer Wt is held by suction by Bernoulli chuck 124, main controller20, as shown in FIG. 26C, rotates the pair of support plates 128integrally with shaft 126 to the first rotating position via the pair ofvertical movement rotation driving sections 127, and also relativelydrives chuck main section 130 and the pair of support plates 128 by apredetermined amount in the Z-axis direction so that chuck main section130 and the pair of support plates 128 are driven in a directionapproaching each other and the pair of support plates 128 come intocontact and support the rear surface of wafer W₁.

Then, main controller 20, as shown in FIG. 26D, separates wafer carrierarm 132 from wafer W₁, and withdraws wafer carrier arm 132 from loadingposition LP. At this point, the movement of the new wafer W₁ indirections of six degrees of freedom is limited by Bernoulli chuck 124and the pair of support plates 128. Incidentally, the separation ofwafer carrier arm 132 from wafer W₁ and the pair of support plates 128coming into contact with wafer W₁ can be reversed in order. In any case,the support state of wafer W₁ is maintained until exposure of thepreceding wafer W has been completed and wafer stage WST returns toloading position LP and the loading of wafer W₁ begins.

The description returns again to describing the concurrent processingoperation. When wafer stage WST moves at a high speed with long strokesin the +Y direction as is previously described, and reaches the positionshown in FIG. 27, measurement stage MST and wafer stage WST moves into acontact or an approaching state. In this contact or approaching state,the end on the −Y side of measurement table MTB and the end on the +Yside of wafer table WTB come into contact or approach each other. Maincontroller 20 drives both stages WST and MST in the +Y direction whilemaintaining the contact or approaching state. With this movement, thewater of liquid immersion area 14 moves from an area on measurementtable MTB to an area on wafer table WTB.

Then when both stages WST and MST reach the position shown in FIG. 29where measurement plate 30 is placed directly under projection opticalsystem PL, main controller 20 stops both stages WST and MST, andperforms the second half processing of Pri-BCHK and the second halfprocessing of focus calibration.

Here, the second half processing of Pri-BCHK refers to a processing inwhich projection images (aerial images) of a pair of measurement markson reticle R (or a mark plate which is not shown on reticle stage RST)projected by projection optical system PL are measured using aerialimage measurement device 45 previously described that includesmeasurement plate 30. In this case, similar to the method disclosed in,for example, U.S. Patent Application Publication No. 2002/0041377, by anaerial image measurement operation of a slit scan method using the pairof aerial image measurement slit patterns SL, the aerial images of thepair of measurement marks are each measured, and the measurement results(the aerial image intensity corresponding to the XY position of wafertable WTB) are stored in memory. On this second half processing ofPri-BCHK, the position of wafer table WTB within the XY-plane ismeasured and controlled based on measurement values of the first finemovement stage position measurement system 110A.

Further, the second half processing of focus calibration refers to aprocessing of measuring the aerial images of the measurement marks onreticle R by a slit scan method using aerial image measurement device 45while controlling the position (Z position) of measurement plate 30(wafer table WTB) in the optical axis direction of projection opticalsystem PL using surface position information measured by the pair of XZheads 65X₂ and 64X₃ that measures the surface position information onthe ends on one side and the other side in the X-axis direction of wafertable WTB, and measuring the best focus position of projection opticalsystem PL based on the measurement results.

On this processing, because liquid immersion area 14 is formed inbetween projection optical system PL and measurement plate 30 (wafertable WTB), the measurement of the aerial images described above isperformed via projection optical system PL and liquid Lq. Further,because measurement plate and the like of aerial image measurementdevice 45 are mounted on wafer stage WST (wafer table WTB), and thephotodetection element and the like are mounted on measurement stageMST, the measurement of the aerial images described above is performedin a state where wafer stage WST and measurement stage MST are incontact or are approaching each other.

According to the measurement described above, measurement values (thatis, surface position information on the ends on one side and the otherside in the X-axis direction of wafer table WTB) of the pair of XZ heads65X₂ and 64X₃ in a state where the center line of wafer table WTBcoincides with reference axis LV is obtained. Such measurement valuescorrespond to the best focus position of projection optical system PL.

After the second half processing of Pri-BCHK and the second halfprocessing of focus calibration described above have been performed,main controller 20 calculates the base line of primary alignment systemAL1, based on results of the first half processing of Pri-BCHK andresults of the second half processing of Pri-BCHK previously described.Further, along with this, main controller 20 adjusts the detectionorigin of the multi-point AF system by obtaining the offset atrepresentative detection points of the multi-point AF system (90 a, 90b) so that the offset becomes zero using the optical method previouslydescribed, based on a relation between measurement values (surfaceposition information on the ends on one side and the other side in theX-axis direction of wafer table WTB) of a pair of XZ heads 66X₁ and 66X₂in a state where the center line of wafer table WTB coincides withreference axis LV obtained in the first half processing of focuscalibration previously described and detection results (surface positioninformation) of a detection point (a detection point located at thecenter or near the center among a plurality of detection points) on thesurface of measurement plate 30 of the multi-point AF system (90 a, 90b), and measurement values (that is, surface position information on theends on one side and the other side in the X-axis direction of wafertable WTB) of the pair of XZ heads 65X₂ and 64X₃ in a state where thecenter line of wafer table WTB coincides with reference axis LV,corresponding to the best focus position of projection optical system PLobtained in the second half processing of focus calibration describedabove.

In this case, from the viewpoint of improving throughput, only one ofthe second half processing of Pri-BCHK and the second half processing offocus calibration described above may be performed, or the operation cango on to the next processing without performing both of the processing.As a matter of course, in the case the second half processing ofPri-BCHK is not performed, the first half processing of Pri-BCHKpreviously described does not have to be performed.

When the operation so far has been completed, main controller 20, asshown in FIG. 30, drives measurement stage MST in the +X direction andalso in the +Y direction, and releases the contact or approaching stateof both stages WST and MST.

Then, main controller 20 performs exposure by a step-and-scan method,and transfers the reticle pattern onto the new wafer w. This exposureoperation is performed by main controller 20 repeating a movementbetween shots in which wafer stage WST is moved to a scanning startingposition (acceleration starting position) for exposure of each shot areaon wafer W, and scanning exposure in which the pattern formed on reticleR is transferred by a scanning exposure method to each shot area, basedon the results (array coordinates of all shot areas on the wafer whichare calculated using an averaged posture obtained from averaging themeasurement results of the entire surface of scales 39 ₁ and 39 ₂previously described as an alignment calculation) of wafer alignment(EGA) which was performed in advance and the latest base line and thelike of alignment system AL1 (and AL2 ₁ to AL2 ₄). Incidentally, theexposure operation described above is performed in a state where liquid(water) Lq is held between tip lens 191 and wafer W.

Further, in the present embodiment, as an example, because the firstshot area which is to be exposed first is decided to the shot areapositioned on the −X side half at the +Y edge of wafer W, first of all,wafer stage WST is moved in the +X direction and also the +Y directionas shown by a black arrow in FIG. 30, so as to move to the accelerationstarting position.

And, along the path shown by a black arrow in FIG. 31, exposure isperformed while moving wafer stage WST in the order from the shot areaat the +Y side to the shot area at the −Y side wafer on the −X side halfof the wafer.

When wafer stage WST moves in the +Y direction along a path shown by theblack arrow in FIG. 31 for exposure of the −X side half of wafer Wdescribed above, the risk of interference with wafer stage WST when Yshape holding section 177 of the second unloading slider 170B whichholds wafer W₀ that has been exposed at standby position UP2 is drivendownward is removed. Therefore, main controller 20, at this point,carries wafer W₀ held by Y shape holding section 177 to a deliveryposition for delivery to the wafer carrier system in the proceduredescribed below, as shown in FIG. 32A.

That is, after main controller 20 drives Y shape holding section 177holding wafer W₀ downward by a predetermined amount via the secondunloading slider driving system 180B as shown by a black arrow in FIG.32B, main controller 20 drives (refer to an outlined arrow in FIG. 31) Yshape holding section 177 in the −Y direction along the first arm 171 asshown by a black arrow in FIG. 32C. When wafer W₀ reaches the positionshown by the broken line in FIG. 31 during this drive, the risk ofinterference with head section 62E and the like when wafer W₀ is liftedupward is removed. Therefore, after the point, main controller 20 moveswafer W₀ to the delivery position for delivery to the wafer carriersystem while driving Y shape holding section 177 holding wafer W₀ upwardby a predetermined amount as shown by two black arrows in FIG. 32D, viathe second unloading slider driving system 180B. In the manner describedabove, wafer W₀ is carried to the delivery position for delivery to thewafer carrier system.

Concurrently with the carriage of wafer W₀ to the delivery positiondescribed above, main controller 20 exposes the +X side half of wafer Win the order from the shot area at the −Y side to the shot area at the+Y side, while moving wafer stage WST along paths shown by black arrowsin FIGS. 33 and 34. By this movement, at the point where exposure of allshot areas on wafer W has been completed, wafer stage WST returnssubstantially to the same position as the position where wafer stage WSTwas before the beginning of exposure.

In the present embodiment, while the exposure order described above ofthe shot areas is employed, the total length of the path in which waferstage WST moves for exposure, in the case a wafer of the same size isexposed according to the same shot map, is not much different from aconventional liquid immersion scanner and the like disclosed in, forexample, U.S. Patent Application Publication No. 2008/0088843 and thelike.

During the exposure described above, of the measurement values of thefirst fine movement stage position measurement system 110A, namely, themeasurement values of four-spindle heads 65 and 64 facing scales 39 ₁and 39 ₂, respectively, or namely, measurement results (measurementvalues of the position) of position information in directions of sixdegrees of freedom measured by the first top side encoder system 80Apreviously described, and the measurement results of the positioninformation (measurement values of the position) in directions of sixdegrees of freedom measured by the first back side encoder system 70A,the measurement value of higher reliability is supplied to maincontroller 20 as the hybrid position signal previously described, andservo control of the position of wafer table WTB is performed based onposition information of wafer table WTB in directions of six degrees offreedom obtained from the hybrid position signal. Further, control ofthe position in the Z-axis direction, θy rotation, and θx rotation ofwafer table WTB (focus-leveling control of wafer W) during this exposureis performed based on results of the focus mapping (surface positioninformation using a scale reference surface as a reference or surfaceposition information using the rear surface measurement referencesurface which has been corrected according to post stream processingresults as a reference) previously described performed in advance.

Further, during the exposure, main controller 20 performs refreshing thecoordinate system of first back side encoder system 70A previouslydescribed according, to difference measurement using measurement valuesof a redundant axis at a predetermined sampling interval, and performsrefreshing the coordinate system at least once of the first top sideencoder system 80A by comparing and adjusting the grids of scales 39 ₁and 39 ₂ to the coordinate system of the first back side encoder system70A having undergone refreshing.

When wafer stage WST moves in the X-axis direction during the exposureoperation by the step-and-scan method described above, with themovement, switching of heads (succession of measurement values among aplurality of heads) previously described is performed in the first topside encoder system 80A. As described, main controller 20 executes stagecontrol by appropriately switching the encoders used of the first topside encoder system 80A, according to the position coordinate of waferstage WST.

Concurrently with the exposure of shot areas on the +X side half of thewafer described above, wafer W₀ having undergone exposure which has beencarried to the delivery position, is delivered to a wafer carrier system(not shown) to be carried outside of the apparatus by a carrier robotnot shown.

When exposure of wafer W is completed, main controller makes wafer stageWST and measurement stage MST which are distanced apart during theexposure move into the contact or approaching state previouslydescribed, by driving measurement stage MST within the XY-plane as shownby an outlined arrow in FIG. 34, based on the measurement values ofmeasurement stage position measuring system 16B. On this shift to thecontact or approaching state, measurement stage MST engages withmeasurement arm 71A laterally (horizontally). In order to allowmeasurement arm 71A to engage with measurement stage MST laterally,measurement table MTB of measurement stage MST is supported on supportsection 62 on slider section 60 in a cantilevered state.

And, main controller 20, as shown in FIG. 35, moves both stages WST andMST in the −Y direction while maintaining the contact or approachingstate described above. This moves (delivers) liquid immersion area 14(liquid Lq) formed under projection unit PU from an area on wafer tableWTB to an area on measurement table MTB.

At the point when delivery of liquid immersion area 14 (liquid Lq)described above from the area on wafer table WTB to the area onmeasurement stage MST has been completed, main controller 20 can controlthe position of measurement stage MST based on measurement values of thefirst back side encoder system 70A which uses grating RGa provided onthe rear surface of measurement table MTB, via measurement table drivingsystem 52B (refer to FIG. 16). Accordingly, main controller 20 canperform necessary measurement operations, while controlling the positionof measurement table MTB in directions of six degrees of freedom.

After moving into the contact or approaching state described above,wafer stage WST moves away from the measurement range of the first finemovement stage position measurement system 110A just before movingliquid immersion area 14 (liquid Lq) from an area on wafer table WTB toan area on measurement table MTB is completed, and position measurementof wafer table WTB by the first top side encoder system 80A and thefirst back side encoder system 70A cannot be performed. Just beforethis, main controller 20 switches the position measurement system usedfor servo control of the position of wafer table WTB from the first finemovement stage position measurement system 110A to the fourth top sideencoder system 80D (three-dimensional heads 79 ₁ and 79 ₂).

Then, wafer stage WST is driven toward unloading position UP1 by maincontroller 20. Accordingly, after the contact or approaching statepreviously described is released, wafer stage WST moves to unloadingposition UP1. Because this movement is performed without liquid Lq beingin contact with the area on wafer table WTB, the movement can beperformed with high acceleration, such as for example, acceleration intwo steps within a short time. When wafer stage WST reaches unloadingposition UP1, main controller 20 unloads wafer W which has been exposedfrom wafer stage WST in the following order.

That is, after main controller 20 releases the suction by the waferholder of wafer W which has been exposed, main controller 20 drives thethree vertical movement pins 140 upward by a predetermined amount andlifts wafer W, as shown by a black arrow in FIG. 36A. The position ofthe three vertical movement pins at this point is maintained until waferstage WST reaches loading position LP, and the loading of the next waferbegins.

Next, main controller 20 drives wafer grasping member 174 of the firstunloading slider 170A downward by a predetermined amount via the firstunloading slider driving system 180A, as shown by an outlined arrow inFIG. 36B. This makes main section 174 a of wafer grasping member 174approach a position at a predetermined distance from wafer W. At thispoint, the four grasping members 174 b of wafer grasping member 174 areopen. Therefore, as shown by black arrows in FIG. 36C, main controller20 closes the four grasping members 174 b via the first unloading sliderdriving system 180A, and drives wafer grasping member 174 upward to apredetermined height position, as shown by an outlined arrow in FIG.36D. By this operation, the four grasping members 174 b of wafergrasping member 174 lift wafer W, in a state where four places on theouter circumference of the rear surface of wafer W are supported frombelow. This completes the unloading of wafer W.

Next, as shown in FIG. 37, main controller 20 drives wafer stage WST ata high speed in a straight line in long steps toward loading positionLP. During this drive, because wafer stage WST moves away from themeasurement range, position measurement of wafer table WTB by the fourthtop side encoder system 80D can no longer be performed. Therefore,before wafer stage WST moves away from the measurement range of thefourth top side encoder system 80D, main controller 20 switches theposition measurement system used for servo control of the position ofwafer table WTB from the fourth top side encoder system 80D to thesecond fine movement stage position measurement system 110B.

Concurrently with moving wafer stage WST to loading position LP, maincontroller 20 moves wafer W held by wafer grasping member 174 of thefirst unloading slider 170A at the predetermined height position ofunloading position UP1 to standby position UP2, as typically shown inFIG. 37 by an outlined arrow. This movement is performed by maincontroller in the following procedure.

That is, as shown by a black arrow in FIG. 38A, main controller 20 movesthe first unloading slider 170A holding wafer W by wafer grasping member174 along the second arm 172, via the first unloading slider drivingsystem 180A, to just above Y shape holding section 177 near a lowerlimit moving position in standby position UP2. And, as shown by a blackarrow in FIG. 38B, main controller 20, for example, drives wafergrasping member 174 holding wafer W downward, via the first unloadingslider driving system 180A, until the rear surface of wafer W comes intocontact with the suction section of Y shape holding section 177. Or,main controller 20, for example, can drive Y shape holding section 177upward via the second unloading slider driving system 180B, until thesuction section of Y shape holding section 177 comes into contact withthe wafer W rear surface held by wafer grasping member 174.

Then, when the rear surface of wafer W comes into contact with thesuction section of Y shape holding section 177, main controller 20 opensthe four grasping members 174 b via the first unloading slider drivingsystem 180A as shown by black arrows in FIG. 38C, and also drives wafergrasping member 174 upward by a predetermined amount, as shown by ablack arrow in FIG. 38D. By this operation, wafer W is delivered fromwafer grasping member 174 to Y shape holding section 177.

After this, main controller 20 returns the first unloading slider 170A(wafer grasping member 174) via the first unloading slider drivingsystem 180A to unloading position UP1 as shown by a black arrow in FIG.38E, and drives Y shape holding section 177 which holds wafer W bysuction from below upward to a position of a predetermined height atstandby position UP2, as shown by an outlined arrow in FIG. 38E. Thestate of this wafer W held by Y shape holding section 177 at theposition of a predetermined height at standby position UP2 is maintaineduntil exposure of the next wafer begins, and wafer stage WST moves to astate withdrawn from below standby position UP2.

This completes a series of processing (one cycle) performed on a wafer,and hereinafter, a similar operation is repeatedly performed.

As is described in detail above, according to exposure apparatus 100related to the present embodiment, the first fine movement stageposition measurement system 110A, which measures the position of wafertable WTB (fine movement stage WFS) held movable in directions of sixdegrees of freedom by coarse movement stage WCS when wafer stage WST isat exposure station 200, is equipped with the first back side encodersystem 70A which measures the position information of wafer table WTB indirections of six degrees of freedom when wafer table WTB moves in apredetermined range within exposure station 200 (a range within exposurestation 200 that includes at least a range where wafer table WTB movesfor exposure of wafer W held by wafer table WTB) by irradiating ameasurement beam from below on grating RG provided on the rear surface(surface on the −Z side) of wafer table WTB and receiving the returnlight (reflected and diffracted light) of the measurement beam fromgrating RG, and is also equipped with the first top side encoder system80A, which has head sections 62A and 62C provided in main frame BD, andcan measure the position information of wafer table WTB in directions ofsix degrees of freedom concurrently with measuring the positioninformation by the first back side encoder system 70A when wafer tableWTB moves in the predetermined range described above within exposurestation 200 by irradiating a measurement beam on the pair of scales 39 ₁and 39 ₂ (two-dimensional gratings) provided on wafer table WTB fromhead sections 62A and 62C and receiving the return light (reflected anddiffracted light) of the measurement beam from scales 39 ₁ and 39 ₂(two-dimensional gratings). And, in the case switching section 150Apreviously described is set to the first mode, when wafer table WTBmoves in the predetermined range described above within exposure station200, such as, for example, at the time of exposure, main controller 20drives, wafer table WTB based on position information having a higherreliability, out of the position information according to the first backside encoder system 70A and the position information according to thefirst top side encoder system 80A. This drive is performed by maincontroller 20 driving coarse movement stage WCS via coarse movementstage driving system 51A, and also servo-driving wafer table WTB viafine movement stage driving system 52A.

Further, in the present embodiment, by setting switching section 150A tothe first mode, output signal F_(B) of the first back side encodersystem 70A and output signal F_(T) of the first top side encoder system80A are switched according to frequency band, with cutoff frequency fc₁and fc₂ previously described serving as a border, and hybrid positionsignal F_(H) of such signals is input to main controller 20. Then, bymain controller 20 driving wafer table WTB within the predeterminedrange described above based on the position information corresponding tohybrid position signal F_(H) previously described, as a consequence,main controller 20 drives wafer table WTB within the predetermined rangedescribed above based on position information having a higherreliability of the position information according to the first back sideencoder system 70A and the position information according to the firsttop side encoder system 80A. Accordingly, it becomes possible to drivewafer table WTB with good precision within the predetermined range inexposure station 200 described above, constantly based on positioninformation having a high reliability.

Further, according to exposure apparatus 100 related to the presentembodiment, the second fine movement stage position measurement system110B, which measures the position of wafer table WTB (fine movementstage WFS) held movable in directions of six degrees of freedom bycoarse movement stage WCS when wafer stage WST is at measurement station300, is equipped with the second back side encoder system 70B whichmeasures the position information of wafer table WTB in directions ofsix degrees of freedom when wafer table WTB moves in a predeterminedrange within measurement station 300 (a range within measurement station300 including at least a range where wafer table WTB moves for streamprocessing and traverse checking previously described, such as, forexample, a range in measurement station 300 corresponding to thepredetermined range previously described in exposure station 200) byirradiating a measurement beam from below on grating RG provided on therear surface (surface on the −Z side) of wafer table WTB and receivingthe return light (reflected and diffracted light) of the measurementbeam from grating RG, and is also equipped with the second top sideencoder system 80B, which has head sections 62F and 62E provided in mainframe BD, and can measure the position information of wafer table WTB indirections of six degrees of freedom concurrently with measuring theposition information by the second back side encoder system 70B whenwafer table WTB moves in the predetermined range described above withinmeasurement station 300 by irradiating a measurement beam on the pair ofscales 39 ₁ and 39 ₂ (two-dimensional gratings) provided on wafer tableWTB from head sections 62F and 62E and receiving the return light(reflected and diffracted light) of the measurement beam from scales 39₁ and 39 ₂ (two-dimensional gratings). And, in the case switchingsection 150B previously described is set to the first mode, when wafertable WTB moves in the predetermined range described above withinmeasurement station 300, such as, for example, at the time of alignment,main controller 20 servo-drives wafer table WTB based on positioninformation having a higher reliability, out of the position informationaccording to the second back side encoder system 70B and the positioninformation according to the second top side encoder system 80B.

Further, in the present embodiment, by setting switching section 150B tothe first mode, output signal F_(B) of the second back side encodersystem 70B and output signal F_(T) of the second top side encoder system80B are switched according to a frequency band, with cutoff frequencyfc₁, fc₂ previously described serving as a border, and hybrid positionsignal F_(H) of such signals is input to main controller 20. And, basedon the position information corresponding to hybrid position signalF_(H) previously described, main controller 20 drives wafer table WTBwithin the predetermined range described above, which, as a consequence,allows wafer table WTB to be driven within the predetermined rangedescribed above based on position information having a higherreliability of the position information according to the second backside encoder system 70B and the position information according to thesecond top side encoder system 80B. Accordingly, it becomes possible todrive wafer table WTB with good precision within the predetermined rangein measurement station 300 described above, constantly based on positioninformation having a high reliability.

Further, according to exposure apparatus 100 related to the presentembodiment, main controller 20 repeatedly performs the refreshingprocessing of the coordinate system of the first back side encodersystem 70A at a predetermined interval (for example, an interval decidedaccording to the request, position control accuracy of wafer table WTBthat is required), when wafer table WTB moves within the predeterminedrange in, exposure station 200 described above at the time of exposureand the like, and the exposure of wafer W is performed while controllingthe position of wafer table WTB on the coordinate system of the firstback side encoder system 70A where the grid error is constantlycorrected. Accordingly, it becomes possible to suppress positionmeasurement errors of wafer table WTB by the first back side encodersystem 70A caused by temporal change and the like of grating RG of thefirst back side encoder system 70A and position control errors based onthe measurement errors, within a permissible level.

Further, main controller 20 performs refreshing the coordinate system ofthe first top side encoder system 80A in which the grid distortion ofthe coordinate system of the first top side encoder system 80A iscalculated backward and revised, based on the grid of the coordinatesystem of the first back side encoder system 70A which is revised, fromthe relation between the partial coordinate systems mutuallycorresponding to the first back side encoder system 70A and the firsttop side encoder system 80A. Accordingly, in the case the position ofwafer table WTB is controlled on the coordinate system of the first topside encoder system 80A, it becomes possible to suppress positionmeasurement errors of wafer table WTB and the position control errorsbased on the measurement errors, within a permissible level.

Further, at the time of stream processing, main controller 20 repeatedlyperforms the refreshing processing of the coordinate system of thesecond back side encoder system 70B at a predetermined interval, andalignment measurement and focus mapping are performed while the positionof wafer table WTB is controlled on the coordinate system of the secondback side encoder system 70B whose grid error is constantly corrected.Further, main controller 20 similarly performs refreshing the coordinatesystem of the second top side encoder system 80B in which the griddistortion of the coordinate system of the second top side encodersystem 80B is calculated backward and revised, based on the revised gridof the coordinate system of the second back side encoder system 70B.Accordingly, similar to the previous description, it becomes possible tosuppress position measurement errors of wafer table WTB by the secondback side encoder system 70B caused by temporal change and the like ofgrating RG of the second back side encoder system 70B, and positioncontrol errors based on the position measurement errors. Further, in thecase the position of wafer table WTB is controlled on the coordinatesystem of the second top side encoder system 80B, it becomes possible tosuppress position measurement errors of wafer table WTB and positioncontrol errors based on the position measurement errors.

Incidentally, to perform the refreshing of the coordinate systems of thefirst and the second back side encoder systems 70A and 70B describedabove with high precision including a higher order element, the markscan be placed in an accurate positional relation and a reference waferwhose surface flatness is extremely high can be prepared, and thisreference wafer can be mounted on wafer table WTB, and wafer table WTBcan be moved within the XY-plane so as to measure the marks of thereference wafer with primary alignment system AL1, as well as measuringthe unevenness of reference wafer using the multi-point AF system (90 a,90 b), while measuring the position of wafer table WTB using the secondback side encoder system 70B, and the measurement (correction) of thecoordinate system of the second back side encoder system 70B, that is,the measurement (correction) including the higher order element of thegrid of grating RG can be performed. This measurement can be performedat least once in the cases such as when starting up a device,theoretically, not on the entire surface of the wafer, but on a partialarea on the wafer. This is because the measurement is performed toobtain data of the higher order element of the grid of grating RGsubject to refreshing, and it is considered that the remaining area canbe corrected by performing the refreshing previously described.

Further, main controller 20 performs the traverse checking previouslydescribed in which errors between the coordinate system at the time ofalignment and the coordinate system at the time of exposure based on theerror factor unique to the stream processing are corrected by actuallymoving wafer stage WST in the X-axis direction, at a frequency decidedin advance (frequency as necessary).

Further, the calculation processing to replace the error factorparameter included in the wafer alignment result (EGA result) and focusmapping result to the corresponding parameter calculated from theaverage of all data observed by the second top side encoder system 80Band the third top side encoder system 80C during the streamingprocessing, that is, the post stream processing previously described isperformed.

Further, according to exposure apparatus 100 related to the presentembodiment, the positional relation in the Y-axis direction betweenprojection optical system PL and the plurality of alignment systems ALG1and ALG2 ₁ to ALG2 ₄ is set so that when wafer stage WST is moved in the+Y direction from loading position LP set on one side (−Y side) in theY-axis direction of measurement station 300 toward exposure station 200and detection of a plurality of (for example, 16) alignment marks on thewafer is performed in this movement path by the plurality of alignmentsystems ALG1, and ALG2 ₁ to ALG2 ₄, none of the parts of wafer stage WSTapproach liquid immersion area 14 until the detection of the pluralityof marks is completed. Further, in addition to the alignment measurementdescribed above, because the stream processing previously describedwhich includes the focus mapping previously described is performedwithout wafer table WTB being in contact with the liquid, the streamprocessing can be performed by moving wafer table WTB (wafer stage WST)with high speed and high acceleration.

Furthermore, because unloading position UP1 is set between the exposureposition and the alignment position, the wafer which has been exposedcan be unloaded immediately from wafer table WTB after the exposure ofthe wafer has been completed, and then wafer table WTB can return toloading position LP. Further, after exposure has been completed, wafertable WTB, after delivering liquid immersion area 14 (liquid Lq) tomeasurement table MTB, returns to unloading position UP1, and then toloading position LP, without coming into contact with the liquid.Accordingly, the movement of wafer table WTB at this point can beperformed with high speed and high acceleration. Furthermore, becauseloading position LP is set on a straight line which connects theexposure position and the alignment position, and also the first halfprocessing of Pri-BCHK is performed at this position, the streamprocessing can be started immediately after the wafer has been loaded onwafer table WTB.

Furthermore, because the order of exposure of the plurality of shotareas on wafer W is from the shot area at the −Y side to the +Y side onthe +X side half (or the −X side half), after the shot area at the +Yside to the −Y side on the −X side half (or the +X side half) has beenexposed, when exposure has been completed, wafer table WTB is located ata position closest to unloading position UP1. Accordingly, afterexposure has been completed, wafer table WTB can be moved to unloadingposition UP1 in the shortest time.

Further, according to exposure apparatus 100 of the present embodiment,main controller 20 can carry the wafer onto wafer table WTB withoutpositional deviation (with good reproducibility) in a state maintaininghigh flatness in the procedure previously described, using chuck unit120 and the three vertical movement pins 140 structured as previouslydescribed. Further, main controller 20 drives fine movement stage WFSbased on the position information measured by the first fine movementstage position measurement system 110A previously described uponexposure of the wafer. Accordingly, exposure of the wafer on finemovement stage WFS in a state where the flatness is maintained high andcarried without any positional deviation can be performed with highprecision.

Further, according to exposure apparatus 100 related to the presentembodiment, chuck main section 130 includes Bernoulli chuck 124 whichholds the wafer in a non-contact manner and cool plate 123 whichcontrols the temperature of the wafer, and the temperature of the waferis controlled to a target temperature until chuck main section 130releases the hold of the wafer. This allows the controlled state of thewafer to the target temperature to be continued until the carriage ofwafer on wafer table WTB is completed.

Further, because chuck unit 120 is equipped with the measurement systemdescribed above including the three imaging devices and signalprocessing system 116, the measurement system can measure the positionaldeviation and rotation errors of the wafer even at the point when thewafer is loaded on wafer table WTB, and by adding this measurementinformation as correction information of the position of the wafer, maincontroller 20 can realize position control (including positioning) witha higher accuracy of wafer W at the time of alignment and/or at the timeof exposure.

As is obvious from the description so far, according to exposureapparatus 100 related to the present embodiment, exposure is performedwith high resolution and good overlay accuracy by liquid immersionexposure to wafer W in a step-and-scan method, based on the highlyprecise results of alignment and focus mapping. Further, even if wafer Wsubject to exposure, for example, is a 450 mm water, a high throughputcan be maintained. To be specific, in exposure apparatus 100, it ispossible to achieve exposure processing to a 450 mm wafer, with equal orhigher throughput to/than the exposure processing to a 300 mm waferusing a liquid immersion scanner as disclosed in U.S. Patent ApplicationPublication No. 2008/0088843 and the like previously described.

Incidentally, in the embodiment above, the case has been described wherein the first fine movement stage position measurement system 110A,switching section 150A is set to the first mode as a method of selectingposition information having a higher reliability from the measurementinformation (position information) by the first back side encoder system70A and the first top side encoder system 80A, and as the positioninformation corresponding to the hybrid position signal previouslydescribed, the position information having a higher reliability isconstantly selected and is used for controlling the position of wafertable WTB. However, in the case it is obvious that reliability is higherfor measurement information (position information) according to thefirst back side encoder system 70A or the first top side encoder system80A as for predetermined operations which involve movement of wafertable WTB, by setting the switching section 151A to the third mode orthe fourth mode previously described during the operation, positioninformation having higher reliability can be used for position controlof wafer table WTB. Or, similar to the embodiment described above, evenin the case when switching the measurement information (positioninformation) between the first back side encoder system 70A and thefirst top side encoder system 80A depending on the situation, it is amatter of course that the switching method is not limited to the methodin the embodiment described above. It is preferable for main controller20 to use position information measured at least by the first top sideencoder system 80A for drive control of wafer table WTB, for example, ina frequency band where reliability of the first back side encoder system70A becomes lower than that of the first top side encoder system 80A bythe vibration of heads 73 a to 73 d (arm member 71) of measurement arm71A, such as, for example, in the frequency band of 50 Hz to 500 Hz,especially in at least a part of 100 Hz to 400 Hz. The reference of theswitching of the measurement information (position information)according to the first back side encoder system 70A and the first topside encoder system 80A is not limited to the frequency band of theoutput signal. In any case, according to the present embodiment, becauseposition measurement of wafer table WTB is possible concurrently by thefirst back side encoder system 70A and the first top side encoder system80A, various usages become possible depending on the good and bad pointssuch as when using only one encoder system, or using both of the systemsand the like. The point is, main controller 20 should control the driveof wafer table WTB by coarse movement stage driving system 51A and/orfine movement stage driving system 52A, based on the positioninformation measured by at least one of the first back side encodersystem 70A and the first top side encoder system 80A. Incidentally, thesame can be said as described above for the second back side encodersystem 70B and the second top side encoder system 80B structuring thesecond fine movement stage position measurement system 110B.

In hybrid control (the first control of switching sections 150A, 150B,and 150C), while the top side encoder system and the back side encodersystem are switched according to vibration, or to be more specific,switched using the low pass filter and the high pass filter having thesame cut off frequency, the present invention is not limited to this,and for example, a hybrid position signal which is a weighted and addedsignal of the output signal of the top side encoder system and theoutput signal of the back side encoder system can also be used. Further,the top side encoder system and the back side encoder system can be usedseparately depending on the cause other than vibration, or can be usedtogether. For example, in the first fine movement stage positionmeasurement system 110A, for example, during the scanning exposure, onlythe back side encoder system 70A can be used.

However, the measurement system which measures the position of wafertable WTB in exposure station 200 does not have to be equipped with thefirst top side encoder system 80, and the system may be equipped withonly the first back side encoder system 70A, or with a combination ofthe first back side encoder system 70A and another measurement system(for example, an interferometer system and the like). When the system isequipped with only the first back side encoder system 70A, as a matterof course, or with a combination of the first back side encoder system70A and another measurement system (for example, an interferometersystem and the like), switching section 150A previously described doesnot necessarily have to be provided. That is, main controller 20constantly measures the position information of wafer table WTB inexposure station 200 using the first back side encoder system 70A andanother measurement system, and position control of wafer table WTB ismainly performed based on the measurement results of the first back sideencoder system 70A, and the measurement results of the interferometersystem and the like can be used secondarily such as for back up in thecase abnormity occurs in the measurement results of encoder system 150.As a matter of course, main controller 20 can measure the positioninformation of wafer stage WST (wafer table WTB) by using both the firstback side encoder system 70A and another measurement system (forexample, an interferometer system and the like) together.

Further, in the embodiment above, a method similar to the one describedabove can be employed in the second fine movement stage positionmeasurement system 110B, for the method of selecting positioninformation having a higher reliability from measurement information(position information) according to the second back side encoder system70B and the second top side encoder system 80B.

Further, in the embodiment described above, while the second finemovement stage position measurement system 110B was equipped with thesecond back side encoder system 70B and the second top side encodersystem 808, the present invention is not limited to this, and themeasurement system to measure the position of wafer table WTB inmeasurement station 300 can have either one of the second back sideencoder system 70B or the second top side encoder system 80B, acombination of one of the encoder systems and another measurementsystem, or an encoder system having a completely different structure, oran interferometer system and the like. As a matter of course, in thecase of only the second top side encoder system 80B, the refreshing ofcoordinate system of the second top side encoder system 80B by thecomparing and adjusting previously described is not performed.

Incidentally, in the embodiment described above, while the case wasdescribed where the first and the second back side encoder systems 70Aand 70B were equipped with measurement arms 71A and 71B having armmembers 71 ₁ and 71 ₂, respectively, in which only at least a part ofthe optical system of an encoder head is incorporated, the presentinvention is not limited to this, and for example, as the measurementarm, as long as a measurement beam can be irradiated from a sectionfacing grating RG, for example, a light source or a photodetector andthe like can be incorporated at the tip of the arm member. In this case,the optical fiber previously described does not have to be arrangedinside of the arm member. Furthermore, the arm member can have any outerand sectional shape, and also does not necessarily have to have adamping member. Further, the first and the second back side encodersystems 70A and 70B do not have to use the inside of arm members 71 ₁and 71 ₂, even in the case the light source and/or the detector are/isprovided in arm members 71 ₁ and 71 ₂.

Further, the first and the second back side encoder systems 70A and 70Bdo not necessarily have to have the measurement arm, as long as thesystems have a head which is placed facing grating RG within the spaceof coarse movement stage WCS, irradiates at least one measurement beamon grating RG and receives light (reflected and diffracted light) fromgrating RG of the measurement beam, and can measure the positioninformation at least within the XY-plane of fine movement stage WFS,based on the output of the head.

Further, in the embodiment described above, while an example was shownof the case where the first and the second back side encoder systems 70Aand 70B each have two three-dimensional heads, an XZ head and a YZ head,it is a matter of course that the combination and placement of the headsare not limited to this. For example, even in the case of performing therefreshing of the coordinate system using the measurement values of theredundant axis, the degrees of freedom which can be measured by thefirst and the second back side encoder systems 70A and 70B does not haveto be set to ten degrees of freedom, and can be degrees of freedom ofseven or more, such as, for example, eight degrees of freedom. Forexample, the systems can have two three-dimensional heads, and only oneof the XZ head and the YZ head. In this case, the placement, thestructure and the like of the heads are not limited to the embodimentdescribed above. For example, the first back side encoder system 70A andthe second back side encoder system 70B can irradiate a plurality ofmeasurement beams on grating RG to measure the position information ofwafer table WTB in directions of six degrees of freedom, and also atleast another measurement beam which is different from theses pluralityof measurement beams, or in other words, the plurality of measurementbeams used for measuring the position information of wafer table WTB indirections of six degrees of freedom is irradiated on grating RG. Insuch a case, main controller 20 can perform a refreshing of thecoordinate system as is previously described using the positioninformation of wafer table WTB measured by the first back side encodersystem 70A and the second back side encoder system 70B according to thedifferent measurement beam, or in other words, can update informationcompensating for the measurement errors of the first back side encodersystem 70A and the second back side encoder system 70B caused by gratingRG.

Further, for example, if the refreshing of the coordinate system usingthe measurement values of the redundant axis previously described is notperformed, the first and the second back side encoder systems 70A and70B can employ a combination and placement of the heads which canmeasure the position information of wafer table WTB only in directionsof six degrees of freedom. For example, the first and the second backside encoder systems 70A and 70B can each have only twothree-dimensional heads. In this case, if the two three-dimensionalheads are placed similarly as in the embodiment above, positioninformation in directions of five degrees of freedom, excluding the θxdirection of wafer table WTB, can be measured. Further, if the twothree-dimensional heads are placed shifted to each other in the X-axisdirection and the Y-axis direction, position information in directionsof six degrees of freedom of wafer table WTB can be measured. Besidesthis, the first and the second back side encoder systems 70A and 70B caneach have a pair of XY heads only, placed in the X-axis direction. Inthis case, measurement of position information in directions of threedegrees of freedom of wafer table WTB within the XY-plane becomespossible. Further, the first and the second back side encoder systems70A and 70B can employ a head section (optical system) which is equippedwith a Z head, other than the X head and/or the Y head.

In the embodiment described above, because grating RG is placed on thelower surface (rear surface) of fine movement stage WFS, fine movementstage WFS can be structured hollow to reduce its weight, and piping,wiring and the like can also be placed inside. The reason for this isbecause, the measurement beam irradiated from the encoder head does notproceed inside fine movement stage WFS, fine movement stage WFS does nothave to be a solid member through which light can be transmitted.However, the present invention is not limited to this, and in the casefine movement stage WFS is a solid member through which light can betransmitted, the grating can be placed on the upper surface of the finemovement stage, that is, the surface facing the wafer, or the gratingcan be formed on the wafer holder which holds the wafer. In the lattercase, even if the wafer holder expands during the exposure, or theloading position with respect to the fine movement stage deviates, suchmovement can be followed, and the position of the wafer holder (wafer)can be measured.

Incidentally, in the embodiment described above, the two-dimensionaldiffraction gratings of scales 39 ₁ and 39 ₂ and grating RG may belocally bent-due to heat generated by each coil unit CUa and CUbstructuring fine movement stage driving system 52A. Similarly, forexample, in the case when a pair each of electromagnets are provided onthe pair of side wall sections 92 a and 92 b of coarse movement stageWCS, respectively, facing the slanted sides of the octagon of finemovement stage WFS, the two-dimensional diffraction gratings of scales39 ₁ and 39 ₂ and grating RG may be locally bent due to heat generatedby the electromagnets. Therefore, a relation between a temperaturechange each coil units CUa and CUb and/or the electromagnets and adistribution of deformation of the two-dimensional diffraction gratingsof scales 39 ₁ and 39 ₂ and grating RG (e.g., a table data which shows arelation between temperature change and deformation distribution) is tobe obtained in advance by analysis. Then, temperature sensors formeasuring the temperature change of each coil units CUa and CUb and/orthe electromagnets can be provided each in the vicinity of thetwo-dimensional diffraction gratings and grating RG, and measurementerrors of the first and the second back side encoder systems 70A and 70Band the first and the second top side encoder system 80A and 80B causedby the local deformation of the two-dimensional diffraction gratings ofscales 39 ₁ and 39 ₂ and grating RG can be corrected, based onmeasurement values of each sensor and the table data described above.

Further, the structures of the first to the fourth top side encodersystems 80A to 80D in the embodiment described above are not limited tothe ones described in the embodiment above. For example, at least a partof the first to the fourth top side encoder systems 80A to 80D canemploy an encoder system which has a structure, as disclosed in, forexample, U.S. Patent Application Publication No. 2006/0227309 and thelike, in which a plurality of encoder head sections (each encoder headsection can be structured, for example, similar to the four-spindle headpreviously described) are provided on wafer table WTB, and facing theseheads a grating section (for example, a two-dimensional grating or aone-dimensional grating section placed two-dimensionally) can beprovided external to wafer table WTB. In this case, the plurality ofencoder head sections can each be placed in the four tips (corners) ofwafer table WTB, or a pair of the encoder head sections can each beplaced outside of wafer table WTB on two diagonal lines intersecting atthe center (the center of the wafer holder), with wafer table WTB inbetween. Further, with the grating section, for example, four gratingplates that each have two-dimensional gratings formed can be attached toa fixed member (such as a plate), and the fixed member can be supportedin a suspended manner by main frame BD by a support member includingflexure so that the four grating plates are placed in the periphery ofprojection optical system PL (or nozzle unit 32).

Incidentally, in the embodiment described above, while fine movementstage WFS is drivable in all of the directions of six degrees offreedom, the present invention is not limited to this, and fine movementstage WFS only has to be driven in at least directions of three degreesof freedom within a two-dimensional plane parallel to the XY-plane. Inthis case, when fine movement stage WFS moves in the predetermined rangewithin exposure station 200 (a range within exposure station 200including at least a range in which fine movement stage WFS moves forexposure of wafer W held on wafer table WTB), main controller 20 candrive fine movement stage WFS while controlling the position indirections of n degrees of freedom (n≧3) including the three degrees offreedom within the two-dimensional plane of fine movement stage WFS, forexample, based on measurement information according to the plurality ofheads of the first back side encoder system 70A, and can update the griderror related to a predetermined measurement direction of the coordinatesystem of the first back side encoder system 70A, based on thedifference between position information related to the predeterminedmeasurement direction which is a part of the position information usedwhen driving fine movement stage WFS in n degrees of freedom, andpositional information different from this which is a redundant positioninformation that is not used when driving fine movement stage WFS in ndegrees of freedom in the predetermined measurement direction. In thiscase, not all of the heads 73 a to 73 d previously described have to beprovided, as long as the position of fine movement stage WFS can bemeasured in each of the X-axis, the Y-axis, and the θz directions offine movement stage WFS, and the grid error in at least one direction ofthe X-axis, the Y-axis, and the Z-axis of the coordinate system of thefirst backside encoder system 70A can be revised, using the measurementvalues of the redundant axis.

Further, fine movement stage driving system 52A is not limited to themoving magnet type system described above, and can also be a moving coiltype system. Furthermore, fine movement stage WFS can be supported incontact by coarse movement stage WCS. Accordingly, the fine movementstage driving system which drives fine movement stage WFS with respectto coarse movement stage WCS, for example, can be a combination of arotary motor and a ball spring (or a feed screw).

Further, in the embodiment described above, while the case has beendescribed where standby position UP2 was set to the −X side of unloadingposition UP1, standby position UP2 does not necessarily have to be set.Further, the structure of unloading device 170 described in theembodiment above is a mere example. For example, on the lower surface ofa side section of frame FL on one side in the X-axis direction and thelower surface of a side section on the other side, a plate shapedsupport member can be installed in a state where it does notinterference with the head section and the like, and on the supportmember at the position of unloading position UP1, a first unloadingslider consisting of a member having a similar structure as wafergrasping member 174 previously described that can move vertically can beprovided, and a second unloading slider can also be structured using arobot arm and the like.

Incidentally, in the embodiment described above, while an example wasdescribed where exposure was performed from the −X side half (or the +Xside half) of wafer W from the shot areas on the +Y side to the shotareas on the −Y side, and then exposure of the +X side half (or the −Xside half) from the shot areas on the −Y side to the shot areas on the+Y side was performed, the order of exposure of the plurality of shotareas on wafer W is not limited to this. After exposure has beencompleted, if wafer table WTB does not have to be moved to the unloadingposition in substantially the shortest time, the plurality of shot areason wafer W can be exposed in an order similar to the one disclosed in,for example, U.S. Patent Application Publication No. 2008/0088843 andthe like, as in a conventional liquid immersion scanner.

Further, in the embodiment described above, because chuck unit 120 wasstructured as previously described, for example, during the exposure ofthe preceding wafer, by making the next wafer wait above loadingposition LP concurrently with the exposure, and controlling thetemperature of the wafer, the wafer whose temperature has beencontrolled can be immediately loaded onto wafer table WTB when waferstage WST returns to loading position LP. However, the structure ofchuck unit 120 is not limited to the structure previously described.Chuck unit 120 (Bernoulli chuck 124) can have, for example, only acarrier function, or in addition to the carrier function, can have atleast one of the temperature control function, the pre-alignmentfunction, and the bending correcting (flattening function), and itsstructure can be decided depending on the type or number of functions tobe added to chuck unit 120 (Bernoulli chuck 124), and the structure toachieve the four functions including the carrier function is not limitedto the ones previously described. For example, in the case such as whenthe next wafer is not waiting above loading position LP concurrentlywith the exposure of the preceding wafer, holding members such as thepair of support plates 128 and the like described above to prevent thepositional deviation within the XY plane of the wafer in a state held ina non-contact manner by chuck main section 130 during the waiting do notnecessarily have to be provided. Further, chuck main section 130 doesnot necessarily have to have a temperature controlling member such ascool plate 123 and the like. For example, in the case when the nextwafer is not waiting above loading position LP concurrently with theexposure of the preceding wafer, a case may be considered wherecontrolling the temperature of the wafer on a cool plate installed at aplace other than the loading position until just before the loadingbegins is sufficient enough. Further, as long as alignment of the wafercan be performed after the loading, the measurement system for measuringthe position information of the wafer while the wafer is being held bychuck main section 130 does not necessarily have to be provided.

Further, in the embodiment described above, while chuck main section 130has Bernoulli chuck 124 consisting of a plate shaped member havingsubstantially the same size as cool plate 123, the present invention isnot limited to this, and instead of Bernoulli chuck 124, chuck mainsection 130 can have a plurality of Bernoulli cups attached directly orvia a plate member to the lower surface of cool plate 123. In this case,the plurality of Bernoulli cups is preferably distributed on the entiresurface, or at least in the center and in the periphery of cool plate123, and it is also preferable that main controller 20 can adjust theblowing, the stopping, the flow volume and/or the flow speed and thelike of a fluid (e.g., air) individually, or for each group (e.g., foreach group in the center and in the periphery). In the case the exposureapparatus is equipped with chuck unit 120 that has chuck main section130 having the structure described above, the flow volume and/or theflow speed of the fluid blowing from at least a part of the plurality ofBernoulli cups of chuck main section 130 can be made different from anormal support state of wafer W to displace at least a part of wafer Wsupported in a non-contact manner in a vertical direction when wafer Wis waiting at the loading position, or at the time of carry-in of waferW onto the wafer holder (wafer table WTB), so that deformation of waferW supported in a non-contact manner from above by chuck main section 130is suppressed. As a matter of course, also in the case when chuck mainsection 130 has a single Bernoulli chuck 124 as in the embodimentdescribed above, in order to suppress the deformation of wafer W, theflow speed and the like of the fluid blowing out from Bernoulli chuck124 can be made different from the normal support state of wafer W. Inany event, in such cases, wafer W whose deformation is suppressed is tobe held by the wafer holder (wafer table WTB).

Incidentally, in the embodiment described above, main controller 20drives chuck main section 130 and the three vertical movement pins 140downward when wafer W, which is supported in a non-contact or contactstate from above and below by chuck main section 130 and the threevertical movement pins 140, is mounted onto the wafer holder (wafertable WTB). However, the present invention is not limited to this, andmain controller 20 can drive the wafer holder (wafer table WTB) upwardwith respect to chuck main section 130 and the three vertical movementpins 140, or can drive chuck main section 130 and the three verticalmovement pins 140 downward while driving the wafer holder (wafer tableWTB) upward. The point is, main controller 20 should relatively movechuck main section 130 and the three vertical movement pins 140 in theZ-axis direction, until the lower surface of wafer W supported fromabove and below by chuck main section 130 and the three verticalmovement pins 140 come into contact with the lower surface of the waferholder (wafer table WTB).

Further, in the embodiment described above, main controller 20 candetect positional deviation in the X-axis direction and the Y-axisdirection and rotation (θz rotation) error of wafer W supported in anon-contact manner by chuck main section 130 using the three imagingdevices 129, before wafer W is supported by the three vertical movementpins 140. In this case, in the case of employing a structure where aposition of chuck main section 130 within the XY plane (includingrotation) is adjustable by driving section 122, the position (includingrotation) of wafer W within the XY plane can be adjusted according tothe positional deviation and the rotation errors which have beendetected. Or, a structure can be employed where the three verticalmovement pins 140 is movable within the XY plane with respect to wafertable WTB, and main controller 20 can adjusts the position (includingrotation) of wafer W within the XY plane according to the positionaldeviation and the rotation errors which have been detected via the threevertical movement pins 140. In the manner described, main controller 20finely adjusts the position of wafer W before wafer W is held by thewafer holder (wafer table WTB).

Further, in the embodiment described above, the case has been describedwhere the three vertical movement pins 140 can vertically moveintegrally with driver 142. However, the present invention is notlimited to this, and the three vertical movement pins 140 can movevertically independently. In such a case, when mounting wafer Wsupported in a non-contact or contact state from above and below bychuck main section 130 and the three vertical movement pins 140 onto thewafer holder (wafer table WTB) as is previously described, by making thetiming of the vertical movement of the three vertical movement pins 140differ, the suction hold of wafer W by the wafer holder chuck can bemade to start from one side toward the other side with a time lag, evenin the case when a uniform pressing force is applied to the wholesurface of wafer W from chuck main section 130. Or, a structure can beemployed where the pressing force pushing in the +Z direction(activating force) of the three vertical movement pins 140 can each beadjusted individually. Also in this case, the suction hold of wafer W bythe wafer holder chuck can be made to start from one side toward theother side with a time lag, even in the case when a uniform pressingforce is applied to the whole surface of wafer W from chuck main section130. In any case, the wafer holder (wafer table WTB) does not have to betilted in the θx and/or the θy directions.

Incidentally, in the embodiment described above, instead of the threevertical movement pins that can support wafer W in contact, for example,one or another plurality of support members that can support wafer Wconcurrently with chuck main section 130 and is vertically movable canbe provided. This plurality of support members can have a structurewhere a part of a side surface of wafer W can be supported, or can havea structure where wafer W can be supported in an opening and closingmanner in the outer circumference at a plurality of places from thesides (and/or from below). This support member can be provided in chuckunit 120 (Bernoulli chuck 124). Further, the member which supports waferW that chuck main section 130 has in a non-contact manner is not limitedto a Bernoulli chuck, and can be any member as long as wafer W can besupported in a non-contact manner. Accordingly, for example, instead of,or with the Bernoulli chuck (or the Bernoulli cup), a vacuum preloadedair bearing can also be used.

Further, in the embodiment described above, an example was given of acase where chuck main section 130 is vibrationally isolated with respectto main frame BD, by fixing driving section 122 to the lower surface ofmain frame BD via a vibration isolation member which is not shown.However, the present invention is not limited to this, and for example,by attaching driving section 122 to frame FL via a support member whichis not shown, chuck main section 130 can be vibrationally isolated withrespect to main frame BD.

Further, in the embodiment described above, while the case has beendescribed where the exposure apparatus has a structure in which one finemovement stage is supported by coarse movement stage WCS and is movedback and forth between measurement station 300 and exposure station 200,the exposure apparatus may have two fine movement stages. In this case,a structure may be added where two fine movement stages can be switchedbetween two coarse movement stages, and the two fine movement stages canalternately be moved back and forth between measurement station 300 andexposure station 200. Or, three or more fine movement stages can beused. Such structures allow concurrent processing of the exposureprocessing to the wafer on one of fine movement stages WFS and thestream processing described above using the other fine movement stageWFS. In this case, one of the two coarse movement stages can be made tobe movable only in exposure station 200, and the other of the two coarsemovement stages can be made to be movable only in measurement station300.

Besides this, instead of measurement stage MST, another wafer stage WSTcan be provided, as disclosed in, for example, U.S. Pat. No. 6,341,007,U.S. Pat. No. 6,262,796 and the like. In this case, it is preferable tostructure coarse movement stage WCS so that it is shaped engageable withmeasurement arm 71A laterally. This allows concurrent processing of theexposure processing to the wafer on one of the wafer stages and thestream processing described above using the other wafer stage.

Second Embodiment

Next, a second embodiment will be described, based on FIG. 39 to FIG.55. Here, components which are the same or similar as in exposureapparatus 100 of the first embodiment previously described will have thesame or similar reference signs, and the description thereabout willalso be simplified or omitted.

FIG. 39 schematically shows a structure in a planar view of an exposureapparatus 1000 related to the second embodiment. Further, FIG. 40 showsa block diagram of an input/output relation of a main controller 20,which mainly structures a control system of exposure apparatus 1000 andhas overall control over each section.

Exposure apparatus 1000 related to the second embodiment is equippedwith two wafer stages WST1 and WST2, instead of wafer stage WSTpreviously described, which are structured similarly to wafer stage WST.Further, in exposure apparatus 1000, components listed in (a) to (j)below differ from exposure apparatus 100 previously described.

(a) Instead of unloading position UP1 and standby position UP2 which areset in between exposure station 200 and measurement station 300, anunloading position UP is set to the same Y position as loading positionLP, at a position a predetermined distance away to the −X side.(b) Due to the position change of unloading position UP described above,the first unloading slider and the second unloading slider that have aspecial structure previously described are removed, and a typical waferunloading member (not shown) consisting of a robot arm such as, forexample, a horizontal multi-joint robot and the like, is provided on the−Y side of base board 12.(c) Secondary alignment systems AL2 ₁ to AL2 ₄ are removed.Incidentally, because the secondary alignment systems no longer exist,hereinafter, primary alignment system AL1 will simply be referred to asalignment system AL1.(d) Light transmitting system 90 a and light receiving system 90 b ofthe multi-point AF system (90 a, 90 b) are placed symmetrical toreference axis LV, between head section 62E and head section 62F. Adetection area AF of the multi-point AF system (90 a, 90 b) is to be anarea having substantially the same length as the length in the X-axisdirection of a shot area on wafer W. The center of such detection areaAF is set to the detection center of alignment system AL1, that is, aposition right above the detection center of three-dimensional head 75 apreviously described. A plurality of detection points of the multi-pointAF system (90 a, 90 b) are placed at a predetermined interval along theX-axis direction within detection area AF on the surface subject todetection. Instead of the multi-point AF system (90 a, 90 b), forexample, a focal position detection system (focal position detectionmechanism) disclosed in the third embodiment of U.S. Pat. No. 4,558,949can be used.(e) According to the structure of the multi-point AF system (90 a, 90 b)described above, especially to the changes in placement, in the secondembodiment, the pair of YZ heads 77 a and 77 b is not provided in armmember 71 ₂ of measurement arm 71B. That is, the third back side encodersystem 70C is not provided. Further, due to this structure, the thirdtop side encoder system 80C is also not provided. Furthermore, thefourth top side encoder system 80D is also not provided.(f) Instead of the third back side encoder system 70C, the third topside encoder system 80C, and the fourth top side encoder system 80Ddescribed above, as shown in FIG. 40, a third fine movement stageposition measurement system 110C, a middle position measurement system121, an exposure coordinate setting measurement system 34, and ameasurement coordinate setting measurement system 35 are provided.Incidentally, the third fine movement stage position measurement system110C, middle position measurement system 121, exposure coordinatesetting measurement system 34, and measurement coordinate settingmeasurement system 35 will be described in detail later on.(g) Wafer stages WST1 and WST2 are each equipped with a Coarse movementstage WCS and a fine movement stage WFS similar to wafer stage WSTpreviously described, and are structured in a similar manner.Hereinafter, wafer tables that fine movement stages WFS of wafer stagesWST1 and WST2 have, respectively, will be referred to as wafer tablesWTB1 and WTB2, respectively, for discrimination. Further, hereinafter,fine movement stages WFS of wafer stages WST1 and WST2, respectively,will also be referred to as wafer tables WTB1 and WTB2, respectively. Inthe second embodiment, wafer stages WST1 and WST2 are drivenindependently within the XY plane by coarse movement stage drivingsystems 51A₁ and 51A₂ which are structured similarly as coarse movementstage driving system 51A previously described. Further, wafer tablesWTB1 and WTB2 are supported in a floating manner in a non-contact statewith respect to coarse movement stages WCS by fine movement stagedriving systems 52A₁ and 52A₂ which are structured similarly as finemovement stage driving system 52A previously described, and are alsodriven in directions of six degrees of freedom in a non-contact manner.(h) Wafer tables WTB1 and WTB2 have the same length in the X-axisdirection as wafer table WTB previously described, as well as a shorterlength in the Y-axis direction. Further, as is obvious when comparingFIGS. 4 and 39, the dimension in the X-axis direction (width) and thedimension in the Y-axis direction (length) of each scale of the pair ofscales 39 ₁ and 39 ₂ provided on the upper surfaces of wafer tables WTB1and WTB2, respectively, are smaller than the dimension in the X-axisdirection (width) and the dimension in the Y-axis direction (length) ofeach scale of the pair of scales 39 ₁ and 39 ₂ that wafer stage WSTpreviously described has.(i) In exposure apparatus 1000 related to the second embodiment, headsections 62A and 62C are equipped with five four-spindle heads 65 ₁ to65 ₅ and 64 ₁ to 64 ₅, respectively, that are placed at an interval WD′(<WD) which is smaller than placement interval WD of four-spindle heads65 ₁ to 65 ₄ and 64 ₁ to 64 ₄ related to the first embodiment previouslydescribed, corresponding to the dimension in the X-axis direction(width) of each scale of the pair of scales 39 ₁ and 39 ₂ describedabove. Four-spindle heads 65 ₁ to 65 ₅ and 64 ₁ to 64 ₅ each include XZhead 65X_(i) and YZ heads 65Y_(i) (i=1 to 5), and XZ head 64X_(i) and YZheads 64Y_(i) which are placed in a positional relation similar to eachfour-spindle head 65 ₁ to 65 ₄ and 64 ₁ to 64 ₄ related to the firstembodiment previously described, and are structured in a similar manner,as shown in FIG. 41. In the second embodiment, the five four-spindleheads 65 ₁ to 65 ₅ structure a multiple-lens (five, in this case) 4-axisencoder, which uses scale 39 ₁ for measuring position information ineach of the X-axis, the Y-axis, the Z-axis, and the θx directions ofwafer table WTB1 and WTB2. Similarly, the five four-spindle heads 64 ₁to 64 ₅ structure a multiple-lens (five, in this case) 4-axis encoder,which uses scale 39 ₂ for measuring position information in each of theX-axis, the Y-axis, the Z-axis, and the θx directions of wafer tableWTB1 and WTB2. And, both of the five-lens 4-axis encoders structure thefirst top side encoder system 80A which measures position information indirections of six degrees of freedom of fine movement stage WFS (namely,wafer table WTB1 or WTB2) supported by coarse movement stage WCS, in thecase when wafer stage WST1 or WST2 is at exposure station 200. Also inthe second embodiment, the placement (including interval WD′ and thelike) of four-spindle heads 65 ₁ to 65 ₅ and 64 ₁ to 64 ₅ and theplacement interval and size of scale 39 ₁ and scale 39 ₂ are decided sothat four-spindle heads 65 ₁ and 64 ₁ (i=1 to 5) measuring the positioninformation of wafer table WTB1 or WTB2 can be sequentially switched toadjacent four-spindle heads, when main controller 20 drives wafer stageWST1 or WST2 in the X-axis direction.(j) Corresponding to the structure of head sections 62A and 62Cdescribed above, as shown in FIG. 39, head sections 62F and 62E thatstructure the second top side encoder system 80B are equipped with fiveeach of four-spindle heads 68 ₁ to 68 ₅ and 67 ₁ to 67 ₅ that are placedat the same Y position in a predetermined interval lined in the X-axisdirection. As shown in FIG. 41, in four-spindle heads 68 ₁ to 68 ₅ and67 ₁ to 67 ₅, XZ heads 68X_(i) and 67X_(i) that the four-spindle headshave, respectively, (to be more precise, irradiation points on scales 39₁ and 39 ₂ of measurement beams emitted by XZ heads 68X_(i) and 67X_(i))are placed along reference-axis LA previously described. Further, XZheads 68X₁ and 67X_(i), and YZ heads 68Y_(i) and 67Y_(i) that structurefour-spindle heads 68 ₁ to 68 ₅, and 67 ₁ to 67 ₅, respectively, areplaced at the same X position as XZ heads 65X_(i) and 64X_(i), and YZheads 65Y_(i) and 64Y_(i) corresponding to four-spindle heads 65 _(i)and 64 _(i) (i=1 to 5), respectively.

Next, the third fine movement stage position measurement system 110Cwill be described. In exposure apparatus 1000 related to the secondembodiment, as shown in FIG. 41, a pair of four-spindle heads 65 ₆ and64 ₆ is placed symmetrically to reference axis LV on the −Y side of eachhead section 62A and 62C. Four-spindle heads 65 ₆ and 64 ₆ are eachstructured in a similar manner as four-spindle heads 65 ₁ to 65 ₅ and 64₁ to 64 ₅. XZ head 65X and YZ head 65Y₆ that structure four-spindle head65 ₆ are placed at the same X position as XZ head 65X₃. XZ head 64X₆ andYZ head 64Y₆ that structure four-spindle head 64 ₆ are placed at thesame X position as XZ head 64X₃.

The pair of four-spindle heads 65 ₆ and 64 ₆ structures a pair ofencoders which measures position information in directions of sixdegrees of freedom of wafer table WTB1 and WTB2 using the pair of scales39 ₁ and 39 ₂, from the beginning of an approaching or a contact state(scrum) of measurement table MTB and wafer tables WTB1 or WTB2 to thebeginning of position measurement of wafer tables WTB1 or WTB2 by thefirst fine movement stage position measurement system 110A which will bedescribed later on, and this pair of encoders structures the third finemovement stage position measurement system 110C (refer to FIG. 40).Measurement values of each encoder structuring the third fine movementstage position measurement system 110C are supplied to main controller20 (refer to FIG. 40).

Next, middle position measurement system 121 (refer to FIG. 40) will bedescribed. Middle position measurement system 121 is a system whichmeasures a position within the XY plane of wafer stage WST1 or WST2 thatis moving when wafer stage WST1 or WST2 moves in between measurementstation 300 and exposure station 200. Middle position measurement system121 has a plurality of Hall elements placed at a predetermined intervalwithin an area between reference-axis LH and reference-axis LA insidebase board 12. Middle position measurement system 121 measures theapproximate position within the XY plane of wafer stage WST1 or WST2using a change in magnetic field occurring by magnets provided on thebottom surfaces of each coarse movement stage WCS, when wafer stage WST1or WST2 moves within the XY plane. Measurement information of thismiddle position measurement system 121 is supplied to main controller 20(refer to FIG. 40). Incidentally, in the present embodiment, no othermeasurement systems are provided for measuring the position of coarsemovement stages WCS of wafer stages WST1 and WST2, other than middleposition measurement system 121 (refer to FIG. 40).

Next, exposure coordinate setting measurement system 34 (refer to FIG.40) will be described. Exposure coordinate setting measurement system 34is placed at a position in the vicinity of exposure station 200, and isused to measure an absolute coordinate of wafer table WTB1 or WTB2 fororigin return of the third fine movement stage position measurementsystem 110C at the point when wafer stage WST1 or WST2 moves from ameasurement station 300 side to an exposure station 200 side and wafertable WTB1 or WTB2 approaches or comes into contact with measurementtable MTB, as it will be described later on. As it will be describedlater on, origin return of the first back side encoder system 70A andthe first top side encoder system 80A of the first fine movement stageposition measurement system 110A is performed, using measurement valuesof the third fine movement stage position measurement system 110C onwhich origin return (reset) has been performed.

Exposure coordinate setting measurement system 34, as shown in FIG. 39,includes a pair of imaging sensors 36 a and 36 b, which is placed atpositions a predetermined distance away to the −Y side (for example, adistance of around one third of the Y-axis direction length of wafertable WTB1) of head sections 62A and 62C, set apart on the +X side andthe −X side of reference axis LV by a same distance which is slightlyshorter than half the length in the X-axis direction of water tableWTB1, a pair of Z sensors 38 a and 38 b which is placed adjacent on the+Y side of the pair of imaging sensors 36 a and 36 b, respectively, anda Z sensor 38 c which is placed set apart to the −Y side of Z sensor 38a, for example, by a distance of around half the length in the Y-axisdirection of wafer table WTB1. These imaging sensors 36 a and 36 b, andZ sensors 38 a to 38 c are each fixed in a suspended manner to mainframe BD, via a support member.

The pair of imaging sensors 36 a and 36 b images marks (not shown) whichare each provided on the edge on both sides in the X-axis direction ofwafer table WTB1 (or WTB2) when wafer table WTB1 (or WTB2) is at apredetermined position, in this case, a position where a state to bedescribed later of approaching or coming into contact with respect tomeasurement table MTB (scrum) begins (scrum starting position), andmeasures the X and the Y positions of the mark subject to imaging, withthe detection center serving as a reference. Z sensors 38 a to 38 c, forexample, consist of heads of optical displacement sensors similar tooptical pick-ups used in CD driving devices and the like that eachmeasure the Z position of the upper surface of wafer table WTB1 (orWTB2). Measurement values of such imaging sensors 36 a and 36 b and Zsensors 38 a to 38 c are supplied to main controller 20.

Accordingly, main controller 20 performs origin return of the third finemovement stage position measurement system 110C, by measuring theposition in directions of six degrees of freedom of wafer table WTB1 orWTB2 simultaneously with exposure coordinate setting measurement system34 and the third fine movement stage position measurement system 110C,and re-setting the measurement values of a pair of encoders consistingof the pair of four-spindle heads 65 ₆ and 64 ₆ that structures thethird fine movement stage position measurement system 110C, using themeasurement values (absolute positions) of imaging sensors 36 a and 36 band Z sensors 38 a to 38 c. Then, after such operation, by making theorigin return of the first back side encoder system 70A and the firsttop side encoder system 80A of the first fine movement stage positionmeasurement system 110A which measures the position of wafer table WTB1(or WTB2) located at exposure station 200 in directions of six degreesof freedom, with the measurement values of the third fine movement stageposition measurement system 110C after the origin return serving as areference, a coordinate system which controls the position of wafertable WTB1 (or WTB2) at the time of exposure (exposure-time coordinatesystem) can be returned.

Next, measurement coordinate setting measurement system 35(refer to FIG.40) will be described. Measurement coordinate setting measurement system35 is placed at a position in the vicinity of measurement station 300,and is used to measure an absolute coordinate of wafer table WTB2 orWTB1 for origin return of the second back side encoder system 70B andthe second top side encoder system 80B of the second fine movement stageposition measurement system 110B, at the point when wafer stage WST2 orWST1 moves to a predetermined position while returning to unloadingposition UP, as it will be described later on.

Measurement coordinate setting measurement system 35, as shown in FIG.39, includes a pair of imaging sensors 36 c and 36 d, which is placed atpositions a predetermined distance away to the +Y side of head sections62F and 62E, set apart from reference axis LV by a same distance whichis slightly shorter than half the length in the X-axis direction ofwafer table WTB2, a pair of Z sensors 38 d and 38 e which is placedadjacent on the +Y side of the pair of imaging sensors 36 c and 36 d,respectively, and a Z sensor 38 f which is placed set apart to the −Yside of Z sensor 38 d, for example, by a distance of around half thelength in the Y-axis direction of wafer table WTB2. Z sensor 38 f isclose to the +Y side of head section 62F. Imaging sensors 36 c and 36 dand Z sensors 38 d to 38 f, are each fixed in a suspended manner to mainframe BD, via a support member.

The pair of imaging sensors 36 c and 36 d images the marks previouslydescribed each provided on the edge on both sides in the X-axisdirection of wafer table WTB2 (or WTB1), and measures the X and the Ypositions of the mark subject to imaging, with the detection centerserving as a reference. Z sensors 38 d to 38 f, for example, consist ofheads of optical displacement sensors similar to Z sensors 38 a to 38 cpreviously described, and each measure the Z position of the uppersurface of wafer table WTB2 (or WTB1). Measurement values of suchimaging sensors 36 c and 36 d and Z sensors 38 d to 38 f are supplied tomain controller 20.

Accordingly, by main controller 20 simultaneously measuring the positionof wafer table WTB2 or WTB1 using measurement coordinate settingmeasurement system 35 and the second fine movement stage positionmeasurement system 110B when wafer stage WST2 or WST1 moves to apredetermined position while returning to unloading position UP as itwill be described later on, and making the origin of the second backside encoder system 70B and the second top side encoder system 80B ofthe second fine movement stage position measurement system 110B returnusing the measurement values (absolute position) of imaging sensor 36 cand 36 d and Z sensors 38 d to 38 f, return of a coordinate system,which controls a position of wafer table WTB2 (or WTB1) at measurementstation 300 at the time when a series of measurements to be describedlater including alignment measurement and the like are performed(measurement-time coordinate system), becomes possible.

Although the description falls out of sequence, in exposure apparatus1000 related to the second embodiment, the first back side encodersystem 70A is structured which measures position information indirections of six degrees of freedom of fine movement stage WFS (wafertable WTB1 or WTB2) using heads 73 a to 73 d incorporated in arm member71 ₁ facing grating RG equipped in fine movement stage WFS supported bycoarse movement stage WCS in exposure station 200, and the first topside encoder system 80A is structured which measures positioninformation in directions of six degrees of freedom of fine movementstage WFS (wafer table WTB1 or WTB2) by head sections 62A and 62C facingthe pair of scales 39 ₁ and 39 ₂, respectively, equipped in finemovement stage WFS supported by coarse movement stage WCS in exposurestation 200, regardless of the presence of wafer stage WST1 or WST2 atexposure station 200.

Further, in exposure apparatus 1000, position information in directionsof six degrees of freedom of fine movement stage WFS (wafer table WTB1or WTB2) supported by coarse movement stage WCS of wafer stage WST1 orWST2 located at exposure station 200 can be measured depending on themode setting of switching section 150A (refer to FIG. 40) by the firstback side encoder system 70A and/or the first top side encoder system80A. In exposure apparatus 1000, main controller 20 performs refreshingof coordinate system of the first back side encoder system 70A in asimilar manner as is previously described. Further, main controller 20updates the grid by comparing and adjusting the grid of the scale of thefirst top side encoder system 80A to the coordinate system of the firstback side encoder system 70A whose grid has been updated by therefreshing of the coordinate system in a similar manner as is previouslydescribed. That is, in the manner described above, refreshing thecoordinate system of the first top side encoder system 80A is performed.

In exposure apparatus 1000 related to the second embodiment, the secondback side encoder system 70B is structured which measures positioninformation in directions of six degrees of freedom of fine movementstage WFS (wafer table WTB1 or WTB2) using heads 75 a to 75 dincorporated in arm member 71 ₂ facing grating RG equipped in finemovement stage WFS supported by coarse movement stage WCS in measurementstation 300, and the second top side encoder system 80B is structuredwhich measures position information in directions of six degrees offreedom of fine movement stage WFS (wafer table WTB1 or WTB2) by headsections 62E and 62F facing the pair of scale 39 ₁, 39 ₂, respectively,equipped in fine movement stage WFS supported by coarse movement stageWCS in measurement station 300, regardless of the presence of waferstage WST1 or WST2 at measurement station 300.

In exposure apparatus 1000, position information in directions of sixdegrees of freedom of fine movement stage WFS (wafer table WTB1 or WTB2)supported by coarse movement stage WCS of wafer stage WST1 or WST2 inmeasurement station 300, can be measured depending on the mode settingof switching section 150B (refer to FIG. 40) by the second back sideencoder system 70B and the second top side encoder system 80B. Inexposure apparatus 1000, main controller 20 performs refreshing of thecoordinate system of the second back side encoder system 70B in asimilar manner as is previously described. Further, main controller 20updates the grid by comparing and adjusting the grid of the scale of thesecond top side encoder system 80B to the coordinate system of thesecond back side encoder system 70B whose grid has been updated by therefreshing of the coordinate system in a similar manner as is previouslydescribed. That is, in the manner described above, refreshing thecoordinate system of the second top side encoder system 80B isperformed.

In the second embodiment, in a state where each wafer stages WST1 andWST2 and measurement stage MST are approaching within a predetermineddistance in the Y-axis direction (including a contact state), aerialimage measurement devices 45 previously described is structured (referto FIG. 40) for each state. However, because aerial image measurementdevice 45 is not structured simultaneously between wafer stage WST1 andmeasurement stage MST and between wafer stage WST2 and measurement stageMST, only one aerial image measurement device 45 is shown in FIG. 40.

To coarse movement stage WCS of wafer stages WST1 and WST2, as shown inFIG. 39, tube carriers TC1 and TC2 are connected, respectively, viapower usage supply tubes 22A and 22B. To wafer stage WST1, tube carrierTC1 which is placed on a guide surface provided separately on the −Xside of base board 12 is connected via tube 22A, and to wafer stageWST2, tube carrier TC2 which is placed on a guide surface providedseparately on the +X side of base board 12 is connected via tube 22B.The two tube carriers TC1 and TC2 are driven in the Y-axis directionfollowing wafer stages WST1 and WST2 by main controller 20, for example,via linear motors and the like. Drive of tube carriers TC1 and TC2 inthe Y-axis direction does not necessarily have to strictly follow thedrive of wafer stages WST1 and WST2 in the Y-axis direction, and onlyhas to follow the drive within a certain permissible range.Incidentally, tube carriers TC1 and TC2 can be placed on base board 12,and in this case, tube carriers TC1 and TC2 can be driven by the planarmotor previously described. The structure and the like of other sectionsare similar to the first embodiment previously described.

Next, a concurrent processing operation using wafer stages WST1 andWST2, and measurement stage MST in exposure apparatus 1000 related tothe second embodiment will be described based on FIGS. 42 to 55. Inthese drawings, illustration of tube carriers TC1, TC2, and base board12 and the like is omitted. Incidentally, during the operation below,main controller 20 controls liquid supply device 5 and liquid recoverydevice 6 of local liquid immersion device 8 as previously described, andthe space directly below tip lens 191 of projection optical system PL isconstantly filled with water. However, hereinafter, to simplify thedescription, description related to control of liquid supply device 5and liquid recovery device 6 will be omitted. Further, while theoperation below will be described using many drawings, the same membermay or may not have the same reference signs in each drawing. That is,although the reference signs written may be different for each drawing,such drawings show the same structure, regardless of the availability ofthe reference signs. The same can be said for each drawing which hasbeen used in the description so far.

Further, while each head of the first and the second back side encodersystems 70A and 70B and the first and the second top side encodersystems 80A and 80B, the AF system, the alignment detection system andthe like are set from an off state to an on state when used or shortlybefore usage, in the description of the operation below, the descriptionthereabout will be omitted.

Further, while refreshing the coordinate system of the first back sideencoder system 70A, and refreshing the coordinate system of the firsttop side encoder system 80A based on this, and refreshing the coordinatesystem of the second back side encoder system 70B, and refreshing thecoordinate system of the second top side encoder system 80B based onthis are performed in a similar manner as is previously described in thefirst embodiment during the concurrent processing operation using waferstages WST1 and WST2 and measurement stage MST also in the secondembodiment, hereinafter, the description thereabout will be omitted.

Further, as a premise, switching sections 150A and 150B are to be set tothe first mode as an example. That is, from the first fine movementstage position measurement system 110A, measurement values correspondingto a hybrid position signal F_(H) of the first back side encoder system70A and the first top side encoder system 80A (hereinafter referred toas a measurement value of the first fine movement stage positionmeasurement system 110A, except for the case when further reference isnecessary), and from the second fine movement stage position measurementsystem 110B, measurement values corresponding to a hybrid positionsignal F_(H) of the second back side encoder system 70B and the secondtop side encoder system 80B (hereinafter referred to as a measurementvalue of the second fine movement stage position measurement system110B, except for the case when further reference is necessary), are eachoutput to main controller 20.

FIG. 42 shows a situation where wafer stage WST2 which holds a waferbefore exposure (referred to as W₂) on which wafer alignment measurementand focus mapping to be described later has been completed waits at apredetermined standby position, and an area on the +X side half of awafer held on wafer table WTB (refer to as W₁) is exposed while waferstage WST1 is moved along a pat shown by a black arrow in FIG. 51 bymain controller 20. The exposure of the area on the +X side half ofwafer W₁ is performed in the order of a shot area on the −Y side to ashot area on the +Y side. Prior to this, exposure of the area on the −Xside half of wafer W₁ is completed while wafer stage WST2 is moved alonga path shown by a black arrow in FIG. 44, in the order of a shot area onthe +Y side to the shot area on the −Y side. By this operation, at thepoint when exposure of all the shot areas of wafer W₁ has beencompleted, wafer stage WST1 returns to substantially the same positionas the position before starting exposure. Incidentally, at this point,the position of wafer stage WST2 is controlled by main controller 20,based on the measurement values of middle position measurement system121 previously described.

In the second embodiment, while the exposure order of shot areasdescribed above is employed, the total length of the path that waferstage WST1 moves for the exposure is not much different from theconventional liquid immersion scanner as is disclosed in, for exampleU.S. Patent Application Publication No. 2008/0088843 and the like, inthe case a wafer of the same size is exposed according to the same shotmap.

During the exposure described above, the measurement values of the firstfine movement stage position measurement system 110A are supplied tomain controller 20, and main controller 20 performs servo-control of theposition of wafer table WTB1. Further, control of the position in theZ-axis direction, the θy rotation and the θx rotation of wafer tableWTB1 during this exposure (focus-leveling control of wafer W) isperformed based on results of focus mapping (to be described later inthe description) performed in advance.

During the exposure operation by the step-and-scan method describedabove, when wafer stage WST1 moves in the X-axis direction, accompanyingthe move, switching of heads of the first top side encoder system 80A(succession of measurement values between a plurality of heads) isperformed. As described, main controller 20 appropriately switches theencoder to be used of the first top side encoder system 80A, and driveswafer stage WST1 according to the position coordinate of wafer stageWST1.

Concurrently with the exposure of the shot areas on the +X side half ofwafer W₁ described above, main controller 20, furthermore, drivesmeasurement stage MST within the XY plane, from a standby position shownby a imaginary line (two-dot chain line) in FIG. 42 to a scrum positionshown by a solid line, based on the measurement values of measurementstage position measurement system 16B (refer to FIG. 40). By this drive,wafer stage WST1 (wafer table WTB1) and measurement stage MST(measurement table MTB) which were distanced from each other duringexposure move into a state where wafer table WTB1 and measurement tableMTB are in contact or approaching (also called a scrum state). Whenmoving into this contact or approaching state, measurement stage MSTengages with measurement arm 71A from the side (laterally).

Next, main controller 20 moves measurement stage MST in the −Y directionand also moves wafer stage WST1 in the −Y direction as well as in the −Xdirection as is shown by two outlined arrows in FIG. 43, whilemaintaining the contact or approaching state of wafer table WTB1 andmeasurement table described above. This moves (delivers) a liquidimmersion area 14 (liquid Lq) formed below projection unit PU from anarea on wafer table WTB1 to an area on measurement table MTB, and liquidimmersion area 14 (liquid Lq) is to be held by projection optical systemPL and measurement table MTB. Further, the reason for moving wafer stageWST1 also in the −X direction in this operation, is so that the nextoperation, namely, an exchanging operation of wafer stage WST1 and waferstage WST2, can be started within a short time after the exposure hasbeen completed.

At the stage when delivery of liquid immersion area 14 (liquid Lq) fromthe area on wafer table WTB1 to the area on measurement table MTBdescribed above has been completed, main controller 20 can control theposition of measurement table MTB via a measurement table driving system52B (refer to FIG. 40), based on measurement values of the first backside encoder system 70A which uses grating RG provided on the rearsurface of measurement table MTB. Accordingly, main controller 20 canperform measurement operations related to exposure that are necessarywhile controlling the position in directions of six degrees of freedomof measurement table MTB.

After moving into the contact or approaching state described above, justbefore finishing to move liquid immersion area 14 (liquid Lq) from thearea on wafer table WTB1 to the area on measurement table MTB, waferstage WST1 moves out of the measurement range of the first fine movementstage position measurement system 110A, and position measurement ofwafer table WTB1 by the first top side encoder system 80A and the firstback side encoder system 70A can no longer be performed. Just beforethis, main controller 20 switches the position measurement system usedto control the position of wafer stage WST1 (wafer table WTB1) from thefirst fine movement stage position measurement system 110A to middleposition measurement system 121 previously described.

Then, as is shown by an outlined arrow in FIG. 44, main controller 20drives wafer stage WST1 in the −X direction to a position where waferstage WST1 no longer faces wafer stage WST2 (refer to FIG. 45), which isstill waiting at the standby position previously described at thispoint.

Next, main controller 20, as is each shown by outlined arrows in FIG.45, drives wafer stage WST2 in the +Y direction concurrently withdriving wafer stage WST1 in the −Y direction. After the contact orapproaching state previously described is released by this drive, waferstage WST1 moves to a position below imaging sensor 36 d and Z sensor 38e previously described, in other words, to a position symmetric to thestandby position of wafer stage WST2 and reference axis LV previouslydescribed (hereinafter, this position will be refer to as a “standbyposition” of wafer stage WST1). Concurrently with this, wafer stage WST2moves to a position where the −X side half of the +Y side surface ofwafer table WTB2 comes into contact or approaches in the Y-axisdirection a −Y side surface of measurement table MTB which holds liquidimmersion area 14 (liquid Lq) along with projection optical system PL(refer to FIG. 46).

Next, as each shown by an outlined arrow in FIG. 46, main controller 20drives wafer stage WST2 in the −X direction, concurrently with drivingwafer stage WST1 in the +X direction. This moves wafer stage WST2 to aposition where imaging sensors 36 a and 36 b and Z sensors 38 a to 38 cof exposure coordinate setting measurement system 34 simultaneously facewafer table WTB2, as well as move wafer stage WST1 to a position w hereimaging sensors 36 c and 36 d and Z sensors 38 d and 38 e of measurementcoordinate setting measurement system 35 simultaneously face wafer tableWTB1, from the standby position described above (refer to FIG. 47).

When wafer stage WST2 moves to the position shown in FIG. 47, maincontroller 20 temporarily switches the position measurement system usedto control the position of wafer table WTB2 (wafer stage WST2) frommiddle position measurement system 121 previously described to the thirdfine movement stage position measurement system 110C. That is, maincontroller 20 performs origin return of the third fine movement stageposition measurement system 110C, by simultaneously measuring theposition in directions of six degrees of freedom of wafer table WTB2with exposure coordinate setting measurement system 34 and the thirdfine movement stage position measurement system 110C, and re-setting themeasurement values of a pair of encoders consisting of the pair offour-spindle heads 65 ₆, 64 ₆ structuring the third fine movement stageposition measurement system 110C, using the measurement values (absolutepositions) of exposure coordinate setting measurement system 34 (imagingsensors 36 a and 36 b and Z sensors 38 a to 38 c). Hereinafter, theposition of wafer table WTB2 is controlled, based on the measurementvalues according to the third fine movement stage position measurementsystem 110C. Further, in a state where wafer stage WST2 is moved to theposition shown in FIG. 47, wafer table WTB2 is in a contact orapproaching state (serum state) in the Y-axis direction with respect tomeasurement table MTB for delivery of the liquid immersion area. Thatis, in the present embodiment, it is decided so that origin return(reset of measurement values) of the third fine movement stage positionmeasurement system 110C is to be performed at the scrum startingposition of wafer table WTB2 to measurement table MTB, and the markpreviously described is provided at a predetermined position on wafertable WTB2 so that the origin return of the third fine movement stageposition measurement system 110C can be performed at this scrum startingposition.

In the second embodiment, in at least a part of a period afterprojection optical system PL and measurement table MTB begins to holdliquid immersion area 14 (liquid Lq) as previously described and untilthe scrum state of wafer table WTB2 to measurement table MTB begins,main controller 20 can perform when necessary at least one measurementrelated to exposure using at least one of a measurement member thatmeasurement table MTB has, namely, illuminance irregularity sensor 95,aerial image measuring instrument 96, wavefront aberration measuringinstrument 97, and illuminance monitor 98 that are previously described,in which illumination light IL is received via a light receiving surfaceof each measuring instrument via projection optical system PL and liquidLq, or in other words, at least one of an uneven illuminancemeasurement, an aerial image measurement, a wavefront aberrationmeasurement and a dose measurement.

Next, main controller 20 drives wafer stage WST2 and measurement stageMST in the +Y direction as is shown by the two outlined arrows pointingupward in FIG. 47, while maintaining the contact or approaching state ofwafer table WTB2 and measurement table MTB. By this drive, liquidimmersion area 14 (liquid Lq) formed below projection unit PU is moved(delivered) from the area on measurement table MTB to the area on wafertable WTB2, and liquid immersion area 14 (liquid Lq) is to be held byprojection optical system PL and wafer table WTB2 (refer to FIG. 49).

At the point when the delivery of liquid immersion area 14 describedabove has been completed, wafer table WTB2 is in a state wheremeasurement arm 71A is inserted into a space of wafer stage WST2, andthe rear surface (grating RG) of wafer table WTB2 faces heads 73 a to 73d of measurement arm 71A, and head sections 62A and 62C face scale 39 ₁and 39 ₂ (refer to FIG. 49). That is, the position of wafer table WTB2can be measured by the third fine movement stage position measurementsystem 110C, as well as by the first fine movement stage positionmeasurement system 110A. Therefore, main controller 20, re-sets themeasurement values of the first back side encoder system 70A and thefirst top side encoder system 80A of the first fine movement stageposition measurement system 110A, based on position coordinates indirections of six degrees of freedom of wafer table WTB2 measured by thethird fine movement stage position measurement system 110C, so as toperform origin return of the first back side encoder system 70A and thefirst top side encoder system 80A. In the manner described, return ofthe exposure-time coordinate system which controls the position of wafertable WTB2 that moves within exposure station 200 is performed.Incidentally, if the position in directions of six degrees of freedom ofwafer table WTB2 by the first fine movement stage position measurementsystem 110A and exposure coordinate setting measurement system 34 can bemeasured simultaneously, the origin of the first back side encodersystem 70A and the first top side encoder system 80A can be returned,according to a method similar to the origin return of the third finemovement stage position measurement system 110C previously described.

After the return of the exposure-time coordinate system described above,main controller 20 controls the position of wafer table WTB2, based onthe measurement values of the first fine movement stage positionmeasurement system 110A.

Concurrently with the drive in the +Y direction of wafer stage WST2 andmeasurement stage MST for the delivery of liquid immersion area 14described above, main controller 20 drives wafer stage WST1 towardunloading position UP (and loading position LP), as shown by an outlinedarrow pointing downward in FIG. 47. Halfway along this drive, positionmeasurement of wafer stage WST1 (wafer table WTB1) by middle positionmeasurement system 121 can no longer be performed. Therefore, beforewafer stage WST1 falls out of the measurement range by middle positionmeasurement system 121, for example, at the point when wafer stage WST1reaches the position shown in FIG. 48, main controller 20 switches theposition measurement system used for controlling the position of wafertable WTB1 (wafer stage WST1) from middle position measurement system121 previously described to the second fine movement stage positionmeasurement system 110B. That is, at the point where wafer stage WST1has reached the position shown in FIG. 48, measurement arm 71B isinserted into a space of wafer stage WST1, and the rear surface (gratingRG) of wafer table WTB1 faces heads 75 a to 75 d of measurement arm 713,and head sections 62F and 62E face scales 39 ₁ and 39 ₂. Further, atthis point, measurement of the absolute position in directions of sixdegrees of freedom of wafer table WTB1 by measurement coordinate settingmeasurement system 35 is possible. Therefore, main controller 20simultaneously measures the position in directions of six degrees offreedom of wafer table WTB1, using measurement coordinate settingmeasurement system and the second fine movement stage positionmeasurement system 110B. And, in a similar manner as is previouslydescribed, main controller 20 re-sets the measurement values of thesecond back side encoder system 70B and the second top side encodersystem 80B of the second fine movement stage position measurement system110B, based on the absolute position of wafer table WTB1 measured bymeasurement coordinate setting measurement system 35, so as to performorigin return of the second back side encoder system 70B and the secondtop side encoder system 80B. In the manner described, return of themeasurement-time coordinate system which controls the position of wafertable WTB1 that moves within measurement station 300 is performed.

Measurement coordinate setting measurement system 35 can measure theabsolute position in directions of six degrees of freedom of wafer tableWTB1, therefore, the switching from middle position measurement system121 to the second fine movement stage position measurement system 110Bdescribed above, namely, the return of the measurement-time coordinatesystem described above, can be performed within a short time.

After the return of the measurement-time coordinate system describedabove, main controller 20 drives wafer stage WST1 in the −Y directionand also in the −X direction as shown by an outlined arrow in FIG. 48,and sets the position to unloading position UP, while controlling theposition of wafer table WTB1 based on the measurement values of thesecond fine movement stage position measurement system 110B (refer toFIG. 49).

At unloading position UP, wafer W₁ which has been exposed is unloadedfrom wafer stage WST1 in the procedure described below. That is, aftersuction of wafer W₁ by a vacuum chuck which is not shown is released, bythe three vertical movement pins 140 (for example, refer to FIG. 20A)moving upward, wafer W₁ is lifted from the wafer holder. Then, the waferunloading member which is not shown is inserted in between wafer W₁ andthe wafer holder, and by the wafer unloading member moving upward by apredetermined amount, wafer W₁ is delivered from the three verticalmovement pins 140 to the wafer unloading member. Then, the waferunloading member carries but the wafer to a delivery position between anexternal carrier system, as is shown by the blackened arrow in FIG. 49.In this case, the three vertical movement pins 140 maintains a state ofbeing driven upward by a predetermined amount in preparation for loadingof the next wafer.

Next, main controller 20 drives wafer stage WST1 in the +X direction bya predetermined amount as is shown by an outlined arrow in FIG. 50, andsets the position of wafer stage WST1 to loading position LP. At loadingposition LP, a new wafer W₃ before exposure (here, as an example, thewafer is to be a wafer in the middle of a lot (1 lot including 25 or 50slices of wafers)) which is supported as is previously described bychuck main section 130 that chuck unit 120 has with its temperaturecontrolled to a predetermined temperature, such as, for example, 23° C.,is loaded onto wafer table WTB1 in the procedure in order previouslydescribed in the first embodiment. FIG. 50 shows a state where a newwafer W₃ before exposure is loaded on wafer table WTB1.

Meanwhile, concurrently with the unloading of wafer W₁, the moving ofwafer stage WST1 to loading position LP, and the loading of wafer W₃,wafer stage WST2 moves toward an exposure starting position of wafer W₂,namely, an acceleration starting position for exposure of the first shotarea, as shown by the two outlined arrows each in FIG. 49 and FIG. 50,while maintaining the contact or approaching state of measurement tableMTB and wafer table WTB2. Prior to beginning this movement to theacceleration starting position, as shown in FIG. 49, in a state wheremeasurement plate 30 of wafer stage WST2 is at a position placeddirectly under projection optical system PL, main controller 20 stopsboth stages WST2 and MST as necessary, and performs the second halfprocessing of BCHK of alignment system AL1 and the second halfprocessing of focus calibration.

When the operations described so far are completed, main controller 20drives measurement stage MST in the +X direction and the +Y direction asshown in FIG. 51, and releases the contact or approaching state of bothstages WST2 and MST.

Then, main controller 20 performs exposure by the step-and-scan method,and transfers the reticle pattern onto the new wafer W₂. This exposureoperation is performed by main controller 20 repeating a movementbetween shots in which wafer stage WST is moved to a scanning startingposition (acceleration starting position) for exposure of each shot areaon wafer W, and scanning exposure in which the pattern formed on reticleR is transferred by a scanning exposure method to each shot area, andscanning exposure in which the pattern formed on reticle R istransferred by a scanning exposure method onto each shot area, based onthe results (array coordinates of all shot areas on the wafer) of waferalignment (EGA) performed in advance and the latest base line and thelike of alignment system ALL. Incidentally, the exposure operationdescribed above is performed in a state where liquid (water) Lq is heldbetween tip lens 191 and wafer W.

Further, in the second embodiment, as an example, because the first shotarea which is to be exposed first is decided to the shot area positionedon the −X side half at the +Y edge of wafer W₂, first of all, waferstage WST is moved in the +X direction and also in the +Y direction soas to move to the acceleration starting position.

And, along a path shown by a black arrow in FIG. 51, exposure isperformed while moving wafer stage WST2 in the order from the shot areaat the +Y side to the shot area at the −Y side on the −X side half ofwafer W₂.

Concurrently with the exposure of the −X side half area of wafer W₂, onthe wafer stage WST1 side, a series of measurement operations which aredescribed below is performed, following the loading operation of waferW₃ previously described.

First of all, when wafer stage WST1 is at loading position LP, the firsthalf processing of base line measurement (BCHK) of alignment system AL1is performed. In the second embodiment, at least a part of the firsthalf processing of BCHK of alignment system AL1 can be performedconcurrently with the loading operation of wafer W₃ previouslydescribed.

Following the first half processing of BCHK of alignment system AL1,when wafer stage WST1 is at loading position LP, the first halfprocessing of focus calibration is performed.

Next, main controller 20 begins focus mapping using the second finemovement stage position measurement system 110B and the multi-point AFsystem (90 a, 90 b).

Now, focus mapping performed in exposure apparatus 1000 related to thesecond embodiment will be described. On this focus mapping, maincontroller 20 mainly controls the position within the XY plane of wafertable WTB1, based on measurement values of the two four-spindle encoders67 and 68 of the second top side encoder system 80B that face scales 39₁ and 39 ₂, respectively.

And, in this state, main controller 20 makes wafer stage WST1alternately repeat a high speed scanning in the −Y direction and the +Ydirection with a step movement in the X-axis direction in between(movement of 1 shot area) as shown by outlined arrows in FIG. 51, takesin position information in the X-axis, the Y-axis, and the Z-axisdirections of both ends in the X-axis direction (the pair of the secondwater-repellent plates 28 b) of the wafer table WTB1 surface (plate 28surface) measured by each of the two four-spindle encoders 67 and 68during the high speed scanning, and position information (surfaceposition information) in the Z-axis direction of the wafer W surfacedetected at each detection point detected by the multi-point AF system(90 a, 90 b), at a predetermined sampling interval, and maps eachinformation taken in mutually and then sequentially stores theinformation in a memory which is not shown.

Then, main controller 20 completes the sampling described above, andthen converts the surface position information on the detection pointsof the multiple point AF system (90 a, 90 b) to data which uses as areference the position information in the Z-axis direction measured byeach of the two four-spindle encoders 67 and 68 simultaneously taken in.Main controller 20 converts the surface position information at eachdetection point of the multi-point AF system (90 a, 90 b) to a surfaceposition data which uses a straight line connecting the surface positionof the left measurement point and the surface position of the rightmeasurement point (table surface reference line) as a reference, similarto the first embodiment previously described. Main controller 20performs such a conversion on all of the information taken in at thetime of sampling.

Now, in exposure apparatus 1000 related to the second embodiment,concurrently with the measurement by the second top side encoder system80B described above, measurement of position information of wafer tableWTB1 (fine movement stage WFS) in the X-axis direction, the Y-axisdirection, the Z-axis direction and θy direction (and θz direction) bythe second back side encoder system 70B can be performed. Therefore, atthe same timing as when the position information in the X-axis, theY-axis, and the Z-axis directions of both ends in the X-axis directionof the wafer table WTB1 surface (plate 28 surface) measured by each ofthe two four-spindle encoders 67 and 68, and position information(surface position information) in the Z-axis direction of the wafer Wsurface detected at each detection point detected by the multi-point AFsystem (90 a, 90 b) are taken in, main controller 20 also takes inmeasurement values of the position in each directions described above(X, Y, Z, θy (and θz)) by the second back side encoder system 70B. And,main controller 20 obtains a relation between data (Z, θy) of the tablesurface reference line that can be obtained from the measurementinformation of the second top side encoder system 80B simultaneouslytaken in; and measurement information (Z, θy) of the second back sideencoder system 70B. This allows the surface position data using thetable surface reference line described above as a reference to beconverted into surface position data using a reference linecorresponding to the table surface reference line described above whichis determined by the Z position and the θy rotation of wafer table WTBobtained by a rear surface measurement (a rear surface measurementreference line), for the sake of convenience).

By acquiring the conversion data described above in advance in themanner described above, for example, on exposure and the like, wafertable WTB1 (or WTB2) surface (a point on the second water-repellentplate 28 b where scale 39 ₂ is formed, and a point on the secondwater-repellent plate 28 b where scale 39 ₁ is formed) is measured by XZheads 64X and 65X as is previously described, and a Z position and atilt with respect to the XY plane (mainly θy rotation) of wafer tableWTB1 (or WTB2) are calculated. By using this Z position and tilt withrespect to the XY plane of wafer table WTB1 (or WTB2) that have beencalculated and the surface position data (surface position data usingthe table surface reference line as a reference) previously described,surface position control of wafer W becomes possible, without actuallyhaving to acquire the surface position information of the wafer W.Accordingly, because the multi-point AF system can be placed at aposition away from projection optical system PL, the focus mapping ofthe second embodiment can be suitably applied, even in the exposureapparatus having a small working distance.

After the focus mapping described above has been completed, waferalignment is performed, for example, by an EGA method. To be morespecific, main controller 20 step drives wafer stage WST1 in the XYtwo-dimensional direction as shown by outlined arrows in FIG. 52 whileperforming servo-control on the position of wafer table WTB, based onthe measurement values of the second fine movement stage positionmeasurement system 110B, and at each stepping position, detects analignment mark arranged in each shot area on the wafer using alignmentsystem AL1, and associates the detection results of alignment system AL1with the measurement values of the second fine movement stage positionmeasurement system 110B at the time of detection and stores theassociated information in memory which is not shown.

Then, main controller 20 performs statistical calculation by the EGAmethod disclosed in, for example, U.S. Pat. No. 4,780,617 usingmeasurement values of the second fine movement stage positionmeasurement system 110B corresponding to the detection results of theplurality of alignment marks obtained in the manner described above, andcalculates EGA parameters (X offset, Y offset, orthogonal degree, waferrotation, wafer X scaling, wafer Y scaling and the like), and obtainsarray coordinates of all the shot areas of wafer W₂ based on thecalculation results. Then, main controller 20 converts the arraycoordinates to a coordinate which uses a position of a fiducial mark FMas a reference. At this point, the exposure of the area on the −X sideof wafer W₂ is still being continued.

In exposure apparatus 1000, because wafer alignment by the EGA method tothe wafer on one of the wafer stages described above is performedconcurrently with the exposure of the wafer on the other wafer stage, itis preferable to perform alignment with as many shot areas serving as asample shot area (alignment shot area). As long as the alignment isperformed concurrently with the exposure of the wafer on the other waferstage, it is preferable to perform the so-called total point EGA whereall shot areas serve as sample shot areas.

Incidentally, in the description above, while the wafer alignment isperformed after the focus mapping has been completed, the description isnot limited to this, and the focus mapping can be performed after thewafer alignment has been completed, or the focus mapping and the waferalignment can be performed partially concurrent.

Then, when the series of measurement operations is completed, maincontroller 20 drives wafer stage WST1 holding wafer W₃ in the −Xdirection and the +Y direction toward the standby position of waferstage WST1, as shown by an outlined arrow in FIG. 53. FIG. 54 shows astate where wafer stage WST1 moves to the standby position and iswaiting at the position. On the way of moving to the standby position,the measurement system used to measure the position of wafer stage WST1is switched from the second fine movement stage position measurementsystem 110B to middle position measurement system 121.

Concurrently with moving wafer stage WST1 to the standby positiondescribed above and the waiting at the standby position thereafter, maincontroller 20 performs exposure of the area on the +X side of wafer W₂held on wafer table WTB2 while moving wafer stage WST2 along a pathshown by a black arrow in each of FIGS. 53, 54, and 55.

As is obvious when comparing FIGS. 55 and 42, while wafer stage WST1 andwafer stage WST2 are switched and the waiting position of wafer stageWST1 is set to a position symmetric about reference axis LV to thewaiting position of wafer stage WST2 in the state shown in FIG. 55, theprogress of the processing of the two wafer Ws held on the two waferstages WST1 and WST2 is the same.

Hereinafter, an operation similar to the described above is repeated bymain controller 20, while alternately using wafer stages WST1 and WST2.

However, on this repetition, when the exposure of wafer W held by waferstage WST2 is completed, wafer stage WST2 is driven in the −Y directionto be replaced with wafer stage WST1, after being driven in the +Xdirection. In this case, wafer stage WST1 is driven in the +Y directionto be replaced with wafer stage WST2.

As described in detail so far, according to exposure apparatus 1000related to the second embodiment, an effect equal to exposure apparatus100 of the first embodiment previously described can be obtained. Inaddition, according to exposure apparatus 1000 related to the secondembodiment, for example, in the case one of the wafer stages WST1 (orWST2) is at exposure station 200, and the other of the wafer stages WST2(or WST1) is at measurement station 300, it becomes possible toconcurrently perform the series of measurement previously described onwafer W held by wafer table WTB2 (or WTB1) in measurement station 300,and to expose wafer W held by wafer table WTB1 (or WTB2) usingillumination light IL via projection optical system PL and liquid Lq inexposure station 200. Further, when exposure to wafer W held by wafertable WTB1 (or WTB2) is completed, delivery of liquid Lq (liquidimmersion area 14) directly below projection optical system PL isperformed between wafer table WTB1 (or WTB2) and measurement table MTB,and the liquid is held by projection optical system PL and measurementtable MTB. It becomes possible to perform this delivery of liquid Lqimmediately after exposure to wafer W held by wafer table WTB1 (or WTB2)has been completed. This frees the apparatus from the operation ofdelivering liquid Lq supplied directly below projection optical systemPL from one of the wafer tables WTB1 or WTB2 to the other of the wafertables. This also eliminates the need of moving wafer table WTB1 (orWTB2) a long way around, for example, as in the case when liquid Lqsupplied directly below projection optical system PL is delivered fromone of the wafer tables WTB1 or WTB2 to the other of the wafer tableswhen wafer table WTB1 (or WTB2) is to be returned to the measurementstation 300 side for wafer exchange and the like. Further, wafer stageWST1 and wafer stage WST2 are moved from one of exposure station 200 andmeasurement station 300 to the other of the exposure station 200 andmeasurement station 300 passing through different movement paths in themiddle area previously described, and in the embodiment, the differentmovement paths means that the position in the X direction is different,that is, the paths are set apart at a side on one end and a side on theother end in the X direction on base board 12. In the embodiment, thetube carrier is connected to wafer stage WST1 from the −X direction, andis connected to wafer stage WST2 from the +X direction; therefore, themovement path of wafer stage WST1 is set on the −X side of projectionoptical system PL in the X direction, and the movement path of waferstage WST2 is set on the +X side of projection optical system PL in theX direction.

Accordingly, throughput can be improved, and the apparatus can also bedownsized.

Further, main controller 20 can perform at least one of an unevenilluminance measurement, an aerial image measurement, a wavefrontaberration measurement and a dose measurement, using at least one of ameasurement member that measurement table MTB has, namely, illuminanceirregularity sensor 95, aerial image measuring instrument 96, wavefrontaberration measuring instrument 97, and illuminance monitor 98 that arepreviously described, in a part of a period after the exposure of waferW held by one of the wafer stages WST1 or WST2 has been completed untilthe exposure of wafer W held by the other of wafer stages WST1 or WST2begins, including, for example, the time described above of replacingthe position in the Y-direction of one of the wafer tables WTB1 or WTB2holding wafer W which has been exposed and the other of the wafer tablesWTB1 or WTB2 holding wafer W on which the series of measurements hasbeen performed. This makes it possible to perform measurement related toexposure when necessary, without reducing the throughput.

Further, according to exposure apparatus 1000 related to the secondembodiment, main controller 20 performs focus mapping and waferalignment measurement while moving wafer stages WST1 and WST2 not onlyin the Y-axis direction, but also in the X-axis direction. This removeserror factors unique to the stream processing, which makes the traversechecking previously described to reduce the influence of the errorfactors unique to the stream processing unnecessary. That is, therelation between the coordinate system of the second fine movement stageposition measurement system 110B (the coordinate system of the secondtop side encoder system 80B and the coordinate system of the second backside encoder system 70B) and the multi-point AF system (90 a, 90 b) andalignment system AL1 does not have to be calibrated.

That is, according to exposure apparatus 1000 related to the secondembodiment, the wafer alignment measurement (EGA) and focus mapping areperformed while making wafer stage WST1 and WST2 move in the X-axisdirection and the Y-axis direction as is previously described, usingalignment system AL1 and the multi-point AF system (90 a, 90 b) whoseposition within the XY plane of each detection center coincides with thedetection center of the second back side encoder system 70B. This meansthat the relation described above between the coordinate system of thesecond fine movement stage position measurement system 110B (thecoordinate system of the second top side encoder system 80B and thecoordinate system of the second back side encoder system 70B) and themulti-point AF system (90 a, 90 b) and alignment system AL1 iscalibrated, naturally, at the time of the wafer alignment measurement(EGA) and the focus mapping. Incidentally, also in the first embodimentpreviously described, a mode can be set of performing the waferalignment measurement (EGA) and the focus mapping by a method similar tothe second embodiment. This removes the error factor unique to thestream processing, and the traverse checking previously described forreducing the influence of the errors unique to the stream processingwill not be required.

Further, according to exposure apparatus 1000 related to the secondembodiment, the positional relation within the XY plane between eachhead of the second back side encoder system 70B, each head of the secondtop side encoder system 80B, and the alignment position (detectioncenter of alignment system AL1) with respect to the detection center ofthe second back side encoder system 70B, is the same or in symmetry asthe positional relation within the XY plane between each head of thefirst top side encoder system 80A, each head of the first back sideencoder system 70A, and the exposure position (the optical axis ofprojection optical system PL, center of exposure area IA) with respectto the detection center of the first back side encoder system 70A. And,at the time of wafer alignment and the like, the position of wafertables WTB1 and WTB2 (that is, wafer) is controlled by themeasurement-time coordinate system whose origin is at the alignmentposition, and at the time of exposure, the position of wafer tables WTB1and WTB2 (that is, wafer) is controlled by the exposure-time coordinatesystem whose coordinate grids correspond to the measurement-timecoordinate system and whose origin is at the exposure position.Accordingly, it becomes possible to control the position of wafer tablesWTB1 and WTB2 (that is, the wafers) with high precision on exposure,based on the measurement results of the wafer alignment and the like.

Incidentally, in the second embodiment described above, while unloadingposition UP is set to in the vicinity of loading position LP at adifferent position, the unloading position and the loading position canbe set to the same position. Further, loading position LP is not limitedto a position set within the field (detection area) of re-alignmentsystem AL1 of fiducial mark FM on measurement plate 30 described above,and can be positioned to a position in the vicinity, for example, at aposition symmetric about reference axis LV to unloading position UP.

Further, in the second embodiment described above, while exposurecoordinate setting measurement system 34 and measurement coordinatesetting measurement system 35 are each equipped with the Z sensor andthe pair of imaging sensors that detect the position of the marks on thewafer table in the X and the Y two-dimensional directions, the presentinvention is not limited to this, and for example, instead of theimaging sensors, an absolute encoder which can measure the absoluteposition of the wafer table in the XY two-dimensional direction can beprovided.

Further, in the second embodiment, while no other measurement systems tomeasure the position information of coarse movement stage WCS areequipped in each of the wafer stages WST1 and WST2 other than the middleposition measurement system, a measurement system for measuring eachposition information of coarse movement stage WCS in measurement station300 and exposure station 200 can be provided separately. Thismeasurement system can be structured, for example, using aninterferometer system, an encoder system, a Hall element sensor similarto middle position measurement system 121, and the like.

Further, in the second embodiment described above, while the third finemovement stage position measurement system 110C, middle positionmeasurement system 121, exposure coordinate setting measurement system34, and measurement coordinate setting measurement system are provided,these systems do not have to be provided, and a measurement device thatcan measure each position information of the two wafer stages WST1 andWST2 within a range when measurement of position information by thefirst and the second back side encoders 70A and 70B and the first andthe second top side encoder systems 80A and 80B cannot be performed,such as for example, the fourth top side encoder system 80D previouslydescribed can be provided. In this case, for example, to the first andthe second top side encoder systems 80A and 80B, heads used forcoordinate setting previously described can be added.

Incidentally, in the second embodiment described above, all measurementoperations using the plurality of measurement members (sensors) ofmeasurement stage MST does not have to be performed during the switchingfrom one of wafer stage WST1 and wafer stage WST2 to the other of waferstage WST1 and wafer stage WST2, and for example, a part of theplurality of measurements can be performed during the switching fromwafer stage WST1 to wafer stage WST2, and the remaining measurements canbe performed during the switching from wafer stage WST2 to wafer stageWST1.

Further, in the first and the second embodiments described above,measurement stage MST does not necessarily have to have the variousmeasurement members (sensors) previously described, and may simply beused instead of the wafer stage to maintain the liquid immersion areabelow projection optical system PL, and in this case, at least a part ofthe various measurement members (sensors) previously described should beprovided on the wafer stage.

Incidentally, in the first embodiment described above, as wafer stageposition measurement system 16A, a Hall element sensor similar to middleposition measurement system 121, or an encoder system and the like canbe used, instead of the interferometer system. That is, in the firstembodiment described above, no interferometer systems need to beprovided. Further, in the first embodiment described above, an exposurecoordinate setting measurement system similar to exposure coordinatesetting measurement system 34 previously described can be provided, andorigin return of at least the first back side encoder system 70A of finemovement stage position measurement system 110A can be performed, usingthe exposure coordinate setting measurement system. Further, in thefirst embodiment described above, a measurement coordinate settingmeasurement system similar to measurement coordinate setting measurementsystem 35 previously described can be provided, and origin return of atleast the second back side encoder system 70B of fine movement stageposition measurement system 110B can be performed, using the measurementcoordinate setting measurement system.

Incidentally, in the first embodiment described above, instead ofunloading position UP1 and standby position UP2 set in between exposurestation 200 and measurement station 300, only the unloading position canbe set in the vicinity of loading position LP, such as for example, aposition having the same Y position as loading position LP and is setapart by a predetermined distance to the −X side. In this case, theunloading position can be set at the same position as loading positionLP. Further, loading position LP is not limited to the position withinthe field (detection area) of primary alignment system AL1 wherefiducial mark FM of measurement plate 30 described above is positioned,and can be a position in the vicinity, such as for example, a positionin symmetry to the unloading position with respect to reference axis LV.

Further, in each of the first and the second embodiments, measurementstage position measurement system 16B which measures the position ofmeasurement stage MST can be a Hall element sensor similar to middleposition measurement system 121 previously described, or an encodersystem, instead of the interferometer system. In the latter case, forexample, as shown in FIG. 56, a two-dimensional grating RG2 can beprovided on the upper surface of measurement table MTB, and facingtwo-dimensional grating RG2, a plurality of encoder heads, such as forexample, a four-spindle head consisting of a combination of an XZ headand a YZ head, can be placed in a plurality of pairs in main frame BDvia a support member, along the movement path of measurement stage MST.In FIG. 56, a pair of four-spindle heads 166 ₁ and 166 ₂, a pair offour-spindle heads 166 ₃ and 166 ₄, and a pair of four-spindle heads 166₅ and 166 ₆ are placed along the movement path of measurement stage MST.These heads and two-dimensional grating RG2 can be referred to togetheras a fifth top side encoder system, and by changing the placement(position) of the heads shown in FIG. 56, or by adding at least onehead, position information of measurement stage MST can be measured bythe fifth top side encoder system during the scrum operation previouslydescribed.

Incidentally, in the first and the second embodiments described above,the structure of the head section and the like of each back side encodersystem is not limited to the ones previously described, and can employany structure. Further, the placement and the number of the heads ineach top side encoder system can be arbitrary.

In the case a measurement system is provided separately to measure theposition of coarse movement stage WCS and fine movement stage WFSseparately, a measurement system which measures a relative positioninformation of coarse movement stage WCS and fine movement stage WFS canbe provided. Similarly, a measurement system which measures relativeposition information of slider section 60 and support section 62 ofmeasurement stage MST and measurement table MTB can also be provided.Further, in the first and second embodiments, wafer stage positionmeasurement system 16A itself does not have to be provided.

Incidentally, in each of the embodiments described above, while the casehas been described where the exposure apparatus is a liquid immersiontype exposure apparatus, besides this, each of the embodiments describedabove can also be suitably applied to a dry type exposure apparatuswhich performs exposure without using liquid (water). For example, inthe case exposure apparatus 1000 related to the second embodiment is adry type exposure apparatus, for example, in the period after exposureof wafer W held by one wafer stage (WST1 or WST2) has been completed andthe one wafer stage moves away from below projection optical system PLuntil exposure of wafer W held by the other wafer stage (WST2 or WST1)begins, main controller 20 can perform a measurement using a measurementmember that measurement table MTB has (that is, at least one ofilluminance irregularity sensor 95, aerial image measuring instrument96, wavefront aberration measuring instrument 97, and illuminancemonitor 98 previously described), related to exposure in whichillumination light IL via projection optical system PL is received vialight receiving surfaces of each measuring instrument, that is, maincontroller 20 can perform at least one of an uneven illuminancemeasurement, an aerial image measurement, a wavefront aberrationmeasurement and a dose measurement. This allows measurement related toexposure be performed as necessary, without reducing the throughput.

Incidentally, in each embodiment described above, while the case hasbeen described where the exposure apparatus is a scanning stepper, thepresent invention is not limited to this, and the embodiment describedabove can also be applied to a static type exposure apparatus such as astepper. Further, the embodiment described above can also be applied toa reduction projection exposure apparatus which employs astep-and-stitch method where a shot area and a shot area aresynthesized.

Further, the projection optical system in the exposure apparatus relatedto each embodiment described above is not limited to a reduction systemand can also be an equal magnifying or a magnifying system, andprojection optical system PL is not limited to the refractive system,and can also be a reflection system or a catadioptric system, and theprojection image can be either an inverted image or an upright image.

Further, illumination light IL is not limited to the ArF excimer laserbeam (wavelength 193 nm), and can also be an ultraviolet light such as aKrF excimer laser beam (wavelength 248 nm), or a vacuum-ultravioletlight such as an F₂ laser beam (wavelength 157 nm). For example, asdisclosed in U.S. Pat. No. 7,023,610, as the vacuum-ultraviolet light, aharmonic wave can also be used which is a single-wavelength laser beamin the infrared or visible range emitted by a DFB semiconductor laser ora fiber laser that is amplified by a fiber amplifier doped with, forexample, erbium (or both erbium and ytterbium), and whose wavelength isconverted into a vacuum-ultraviolet light using a nonlinear opticalcrystal.

Further, in each embodiment described above, it is a matter of coursethat illumination light IL of the exposure apparatus is not limited tolight having a wavelength of 100 nm or over, and light having awavelength less than 100 nm can also be used. For example, theembodiment above can be suitably applied to an EUV (Extreme Ultraviolet)exposure apparatus that uses an EUV light in a soft X-ray range (forexample, a wavelength range of 5 to 15 nm). In addition, each embodimentabove can also be applied to an exposure apparatus that uses chargedparticle beams such as an electron beam or an ion beam.

Further, in each embodiment described above, while a light transmissivetype mask (reticle) in which a predetermined light-shielding pattern (ora phase pattern or a light-attenuation pattern) is formed on alight-transmitting substrate is used, instead of this reticle, asdisclosed in, for example, U.S. Pat. No. 6,778,257, an electron mask(which is also called a variable shaped mask, an active mask or an imagegenerator, and includes, for example, a DMD (Digital Micro-mirrorDevice) that is a type of a non-emission type image display element(spatial light modulator) or the like) on which a light-transmittingpattern, a reflection pattern, or an emission pattern is formedaccording to electronic data of the pattern that is to be exposed canalso be used. In the case of using such a variable shaped mask, becausethe stage on which the wafer or the glass plate and the like is mountedis scanned with respect to the variable shaped mask, by measuring theposition of this stage using the first and the second fine movementstage position measurement systems 110A and 110B previously described,an effect equal to the embodiment described above can be obtained.

Further, as disclosed in, for example, PCT International Publication No.2001/035168, the embodiment described above can also be applied to anexposure apparatus (lithography system) which forms a line-and-spacepattern on wafer W by forming an interference fringe on wafer W.

Furthermore, as disclosed in, for example, U.S. Pat. No. 6,611,316, eachembodiment described above can also be applied to an exposure apparatusthat synthesizes two reticle patterns on a wafer via a projectionoptical system, and by performing scanning exposure once, performsdouble exposure of one shot area on the wafer almost simultaneously.

Incidentally, in each embodiment described above, the object (the objectsubject to exposure on which an energy beam is irradiated) on which thepattern is to be formed is not limited to a wafer, and may be anotherobject such as a glass plate, a ceramic substrate, a film member, or amask blank and the like.

Furthermore, the usage of the exposure apparatus is not limited to theexposure apparatus used for producing semiconductor devices, and forexample, the exposure apparatus can also be widely applied to anexposure apparatus for liquid crystal displays used to transfer a liquidcrystal display device pattern on a square shaped glass plate, or anexposure apparatus used to manufacture an organic EL, a thin filmmagnetic head, an imaging device (such as a CCD), a micromachine, a DNAchip and the like. Further, each embodiment described above can also beapplied not only to an exposure apparatus for producing microdevicessuch as semiconductor devices, but also to an exposure apparatus whichtransfers a circuit pattern on a glass substrate or a silicon wafer, inorder to manufacture a reticle or a mask used in a light exposureapparatus, an EUV exposure apparatus, an X-ray exposure apparatus, andan electron beam exposure apparatus and the like.

Electronic devices such as semiconductor devices are manufacturedthrough the following steps; a step where the function/performancedesign of the device is performed, a step where a reticle based on thedesign step is manufactured, a step where a wafer is manufactured fromsilicon materials, a lithography step where the pattern of a mask(reticle) is transferred onto the wafer by the exposure apparatus(pattern formation apparatus) related to the embodiment previouslydescribed and an exposure method corresponding thereto, a developmentstep where the wafer that has been exposed is developed, an etching stepwhere an exposed member of an area other than the area where the resistremains is removed by etching, a resist removing step where the resistthat is no longer necessary when etching has been completed is removed,a device assembly step (including a dicing process, a bonding process,and a package process), an inspection step and the like. In this case,in the lithography step, because the device pattern is formed on thewafer by executing the exposure method previously described using theexposure apparatus in the embodiment described above, a highlyintegrated device can be produced with good productivity.

Further, the exposure apparatus (pattern formation apparatus) of theembodiment above is manufactured by assembling various subsystems, whichinclude the respective constituents that are recited in the claims ofthe present application, so as to keep predetermined mechanicalaccuracy, electrical accuracy and optical accuracy. In order to securethese various kinds of accuracy, before and after the assembly,adjustment to achieve the optical accuracy for various optical systems,adjustment to achieve the mechanical accuracy for various mechanicalsystems, and adjustment to achieve the electrical accuracy for variouselectric systems are performed. A process of assembling varioussubsystems into the exposure apparatus includes mechanical connection,wiring connection of electric circuits, piping connection of pressurecircuits, and the like among various types of subsystems. Needless tosay, an assembly process of individual subsystem is performed before theprocess of assembling the various subsystems into the exposureapparatus. When the process of assembling the various subsystems intothe exposure apparatus is completed, a total adjustment is performed andvarious kinds of accuracy as the entire exposure apparatus are secured.Incidentally, the making of the exposure apparatus is preferablyperformed in a clean room where the temperature, the degree ofcleanliness and the like are controlled.

Incidentally, the disclosures of the PCT International Publications, theU.S. Patent Application Publications and the U.S. Patents that are citedin the description so far related to exposure apparatuses and the likeare each incorporated herein by reference.

While the above-described embodiments of the present invention are thepresently preferred embodiments thereof, those skilled in the art oflithography systems will readily recognize that numerous additions,modifications, and substitutions may be made to the above-describedembodiments without departing from the spirit and scope thereof. It isintended that all such modifications, additions, and substitutions fallwithin the scope of the present invention, which is best defined by theclaims appended below.

What is claimed is:
 1. An exposure apparatus which exposes an object byan energy beam via an optical system, the apparatus comprising: a movingmember holding the object which is movable along a predetermined planeincluding a first axis and a second axis orthogonal to each other, andhas a first grating provided at a position on an opposite side of theoptical system with respect to a surface on which the object is mounted;a first measurement system which measures a first position informationof the moving member by irradiating a first measurement beam from belowon the first grating and receiving light from the first grating of thefirst measurement beam, when the moving member moves in a firstpredetermined range within the predetermined plane; a second measurementsystem which has a head provided in one of the moving member and outsideof the moving member, and can measure a second position information ofthe moving member concurrently with measurement of the first positioninformation by the first measurement system by irradiating a secondmeasurement beam on a second grating provided on the other of the movingmember and outside of the moving member from the head and receivinglight from the second grating of the second measurement beam, when themoving member moves in the first predetermined range within thepredetermined plane; and a driving system which drives the moving memberwithin the first predetermined range, based on position informationhaving a higher reliability of the first position information and thesecond position information.
 2. The exposure apparatus according toclaim 1 wherein the moving member structures a part of a movable bodywhich has a space inside and moves at least along the predeterminedplane.
 3. The exposure apparatus according to claim 2 wherein themovable body includes a movable member which has a space inside and canmove at least along the predetermined plane, and the moving membersupported movable within a plane parallel to the predetermined plane bythe movable member.
 4. The exposure apparatus according to claim 2wherein the first measurement system has a first measurement arm whichis supported in a cantilevered state extending in the first directionand can be inserted into the space from one side of a first directionparallel to the first axis, and irradiates the first measurement beam onthe first grating from below and receives light from the first gratingof the first measurement beam.
 5. The exposure apparatus according toclaim 4 wherein the driving system measures position information of themoving member, by switching between the first measurement system and thesecond measurement system at a first cutoff frequency which is slightlylower than a frequency band of background vibration acting on the firstmeasurement arm.
 6. The exposure apparatus according to claim 5 whereinthe driving system measures position information of the moving member byswitching between the second measurement system and the firstmeasurement system at a second cutoff frequency whose frequency band ishigher than the frequency band of background vibration.
 7. The exposureapparatus according to claim 4 wherein the driving system can be set toa plurality of modes which include a switching mode between the firstmeasurement system and the second measurement system according to afrequency band of an output signal as one mode.
 8. The exposureapparatus according to claim 4 wherein the first predetermined range isa range within an exposure station in which the object is exposed by theenergy beam.
 9. The exposure apparatus according to claim 8 wherein thesecond grating is provided on the moving member, the apparatus furthercomprising: a third measurement system which measures a third positioninformation of the moving member at least within the predetermined planeby irradiating a third measurement beam from below on the first gratingand receiving light from the first grating of the third measurementbeam, when the moving member moves in a second predetermined rangedifferent from the first predetermined range within the predeterminedplane; and a fourth measurement system which has a head provided outsideof the moving member, and measures a fourth position information of themoving member at least within the predetermined plane concurrently withmeasurement of the third position information by the third measurementsystem by irradiating a fourth measurement beam from the head on thesecond grating and receiving light from the second grating, when themoving member moves in the second predetermined range, whereby thedriving system drives the moving member within the second predeterminedrange, based on position information having a higher reliability of thethird and fourth position information.
 10. The exposure apparatusaccording to claim 9 wherein the third measurement system has a secondmeasurement arm which is supported in a cantilevered state extending inthe first direction and is insertable into the space from one side ofthe first direction that irradiates the third measurement beam on thefirst grating from below and receives light from the first grating ofthe third measurement beam.
 11. The exposure apparatus according toclaim 10 wherein the second measurement arm has an arm member supportedin a cantilevered state, and a plurality of heads having at least a partof the heads provided on a plane on a side facing the first grating ofthe arm member, each head measuring position information of the movingmember in at least one measurement direction, with the measurementdirection being the first direction, a second direction parallel to thesecond axis, and a third direction orthogonal to the predeterminedplane, by each irradiating the third measurement beam on the firstgrating and receiving light from the first grating of the thirdmeasurement beam, whereby the third measurement system measures positioninformation of the moving member in at least six degrees of freedom,based on measurement information by the plurality of heads.
 12. Theexposure apparatus according to claim 11 wherein the arm member has anunequal sectional shape whose fixed end is larger than a free end. 13.The exposure apparatus according to claim 11 wherein the arm member ishollow.
 14. The exposure apparatus according to claim 11 wherein the armmember is made of a low thermal expansion material.
 15. The exposureapparatus according to claim 11 wherein a damping member is attached tothe free end of the arm member.
 16. The exposure apparatus according toclaim 11 wherein the plurality of heads of the third measurement systemincludes a pair of three-dimensional heads which measures positioninformation of the moving member in the first direction, the seconddirection, and the third direction, with two points which are positionedat the same position in the first direction and whose positions aredifferent in the second direction serving as each measurement point. 17.The exposure method according to claim 16, the apparatus furthercomprising: a mark detection system whose detection center is placed onone side of the first direction from an exposure position where theenergy beam is irradiated on the object, and detects a mark provided onthe object.
 18. The exposure apparatus according to claim 17 wherein ameasurement point of one of the pair of three-dimensional heads of thethird measurement system coincides with the detection center of the markdetection system.
 19. The exposure apparatus according to claim 17wherein two points symmetric in the second direction with respect to thedetection center of the mark detection system serve as measurementpoints of the pair of three-dimensional heads of the third measurementsystem.
 20. The exposure apparatus according to claim 19 wherein thesecond predetermined range is a range in a measurement station wheremark detection of a mark on the object by the mark detection system isperformed.
 21. The exposure apparatus according to claim 17 wherein thesecond predetermined range is a range in a measurement station wheremark detection of a mark on the object by the mark detection system isperformed.
 22. The exposure apparatus according to claim 21, theapparatus further comprising: a surface position detection system whichdetects surface position information of the object in the thirddirection serving as an optical axis direction of the optical system,wherein detection center of the surface position detection systemcoincides with the detection center of the mark detection system. 23.The exposure apparatus according to claim 22 wherein the surfaceposition detection system has a plurality of detection points set withina detection area whose center is the detection center.
 24. The exposureapparatus according to claim 41 wherein detection of a mark on theobject by the mark detection system is performed while moving the movingmember holding the object, within the predetermined plane, alongdirections parallel to the first axis and the second axis, respectively.25. The exposure apparatus according to claim 24 wherein detection of amark on the object by the mark detection system is performed whilemoving the moving member holding the object, within a range whichsubstantially covers a range where the moving member holding the objectis moved at the time of exposure of the object.
 26. The exposureapparatus according to claim 21 wherein detection of a surface positioninformation of the object by a surface position detection system isperformed while moving the moving member holding the object within thepredetermined plane, along directions parallel to the first axis and thesecond axis, respectively.
 27. The exposure apparatus according to claim26 wherein the detection of the surface position information of theobject by the surface position detection system is performed whilemoving the moving member holding the object, within a range whichsubstantially covers a range where the moving member holding the objectis moved at the time of exposure of the object.
 28. The exposureapparatus according to claim 21, the apparatus further comprising: anintermediate measurement system which measures position informationwithin the predetermined plane of the moving member located in a middlearea between the exposure station and the measurement station, whereinthe driving system drives the moving member along a predeterminedmovement path within the middle area, based on the position informationmeasured by the intermediate measurement system.
 29. The exposureapparatus according to claim 28, the apparatus further comprising: afirst coordinate return measurement system provided for origin return ofthe first measurement system which measures an absolute coordinate ofthe moving member that has moved from the measurement station side tothe exposure station side.
 30. The exposure apparatus according to claim29 wherein the absolute coordinate measured by the first coordinatereturn measurement system is also used for origin return of the secondmeasurement system.
 31. The exposure apparatus according to claim 29wherein the first coordinate return measurement system includes atwo-dimensional image sensor which detects a mark provided on the movingmember.
 32. The exposure apparatus according to claim 31 wherein thefirst coordinate return measurement system further includes a positionsensor which measures a position in a direction orthogonal to thepredetermined plane of the moving member.
 33. The exposure apparatusaccording to claim 29, the apparatus further comprising: a secondcoordinate return measurement system provided for origin return of thethird measurement system which measures an absolute coordinate of themoving member that has moved from the exposure station side to themeasurement station side.
 34. The exposure apparatus according to claim33 wherein the second coordinate return measurement system includes atwo-dimensional image sensor which detects a mark provided on the movingmember.
 35. The exposure apparatus according to claim 34 wherein thesecond coordinate return measurement system further includes a positionsensor which measures a position in a direction orthogonal to thepredetermined plane of the moving member.
 36. The exposure apparatusaccording to claim 33 wherein the absolute coordinate measured by thesecond coordinate return measurement system is also used for originreturn of the fourth measurement system.
 37. The exposure apparatusaccording to claim 21 wherein a first moving member and a second movingmember that each hold the object and are driven independent from eachother within the predetermined plane by the driving system are providedas the moving member, whereby the first moving member and the secondmoving member are driven so that concurrently with an exposure performedon an object held by one of the first moving member and the secondmoving member in the exposure station, a predetermined measurementincluding detection of a mark on an object held by the other of thefirst moving member and the second moving member by the mark detectionsystem is performed in the measurement station.
 38. The exposureapparatus according to claim 16 wherein the plurality of heads of thethird measurement system further includes a first two-dimensional headwhose measurement point is a point which is positioned on one side inthe first direction of a measurement point of one of the pair ofthree-dimensional heads, with the first direction and the thirddirection serving as measurement directions.
 39. The exposure apparatusaccording to claim 38 wherein the plurality of heads of the thirdmeasurement system further includes a second two-dimensional head whosemeasurement point is a point which is positioned on one side in thefirst direction of the other of the pair of three-dimensional heads,and, is positioned at the same position as the measurement point of thefirst head in the second direction, with the second direction and thethird direction serving as measurement directions.
 40. The exposureapparatus according to claim 11 wherein the third measurement systemmeasures position information of the moving member in degrees of freedomof more than six, based on measurement information by the plurality ofheads of the third measurement system, whereby the driving systemupdates grid errors in the predetermined measurement direction of thecoordinate system of the third measurement system when the moving membermoves in the second predetermined range, based on a difference betweenposition information of the moving member in a predetermined measurementdirection which is a part of position information used to drive themoving member in six degrees of freedom and another position informationwhich is redundant position information of the moving member in thepredetermined measurement direction that is not used when driving themoving member in the six degrees of freedom.
 41. The exposure apparatusaccording to claim 40 wherein the driving system calculates backward andupdates a grid distortion of the fourth coordinate system, based on agrid of a coordinate system of the third measurement system, from arelation between partial coordinate systems that mutually correspond tothe fourth measurement system and the third measurement system.
 42. Theexposure apparatus according to claim 11, the apparatus furthercomprising: a surface position detection system which detects surfaceposition information of the object in the third direction, which is anoptical axis direction of the optical system, wherein the plurality ofheads of the third measurement system further includes a pair oftwo-dimensional heads which measures position information of the movingmember in the second and the third directions, with two points on astraight line in the second direction that passes through a detectioncenter of the surface position detection system serving as each of theirmeasurement points.
 43. The exposure apparatus according to claim 8wherein the second grating is provided outside of the movable body, andthe head irradiating the second measurement beam on the second gratingis provided on the movable body, and the apparatus further comprising: athird measurement system which measures a third position information ofthe moving member by irradiating a third measurement beam from below onthe first grating and receiving light from the first grating of thethird measurement beam, when the moving member moves in a secondpredetermined range different from the first predetermined range withinthe predetermined plane; and a fourth measurement system which measuresa fourth position information of the moving member by irradiating thesecond measurement beam on a third grating provided outside of themoving member from the head and receiving light from the third grating,when the moving member moves within the second predetermined range,whereby the driving system drives the moving member within the secondpredetermined range, based on position information having a higherreliability of the third and fourth position information.
 44. Theexposure apparatus according to claim 4, the apparatus furthercomprising: another movable body which is movable along thepredetermined plane independently from the moving member, having atleast a part of the another movable body that can face the firstmeasurement arm and a two-dimensional grating provided on its facingsection.
 45. The exposure apparatus according to claim 44 wherein theanother movable body has a sectional shape engageable to the firstmeasurement arm from a direction intersecting the first direction. 46.The exposure apparatus according to claim 44 wherein the another movablebody has a measurement member.
 47. The exposure apparatus according toclaim 1 wherein the first grating is a two-dimensional grating having apredetermined area, placed on the rear surface of the moving member. 48.The exposure apparatus according to claim 47 wherein the firstmeasurement arm has an arm member supported in a cantilevered state, anda plurality of heads that has at least a part of the heads provided on asurface of the arm member on a side which can face the first grating,and each irradiate the first measurement beam on the first grating,receive light from the first grating of the first measurement beam, andmeasure position information of the moving member in a measurementdirection, with at least one of the first direction, a second directionparallel to the second axis, and a third direction orthogonal to thepredetermined plane serving as the measurement direction, whereby thefirst measurement system measures position information of the movingmember in at least six degrees of freedom, based on measurementinformation by the plurality of heads.
 49. The exposure apparatusaccording to claim 48 wherein the arm member has an unequal sectionalshape whose fixed end is larger than a free end.
 50. The exposureapparatus according to claim 48 wherein the arm member is hollow. 51.The exposure apparatus according to claim 48 wherein the arm member ismade of a low thermal expansion material.
 52. The exposure apparatusaccording to claim 48 wherein a damping member is attached to the freeend of the arm member.
 53. The exposure apparatus according to claim 48wherein the plurality of heads includes a pair of three-dimensionalheads which measures position information of the moving member in thefirst direction, the second direction, and the third direction, with twopoints which are positioned at the same position in the first directionand whose positions are different in the second direction serving aseach measurement point.
 54. The exposure apparatus according to claim 53wherein a point directly below an irradiation position of the energybeam serves as the measurement point of one of the pair ofthree-dimensional heads.
 55. The exposure apparatus according to claim53 wherein two points symmetrical in the second direction with respectto an irradiation position of the energy beam serve as the measurementpoint of each of the pair of three-dimensional heads.
 56. The exposureapparatus according to claim 53 wherein the plurality of heads furtherinclude a first head whose measurement point is a point which ispositioned on one side in the first direction of a measurement point ofone of the pair of three-dimensional heads, with the first direction andthe third direction serving as measurement directions.
 57. The exposureapparatus according to claim 56 wherein the plurality of heads furtherincludes a second head whose measurement point is a point which ispositioned on one side in the first direction of the other of the pairof three-dimensional heads and is positioned at the same position as themeasurement point of the first head in the second direction, with thesecond direction and the third direction serving as measurementdirections.
 58. The exposure apparatus according to claim 57 wherein thedriving system updates grid errors in the second direction at eachposition in the first direction of the coordinate system of the firstmeasurement system, based on measurement information in the seconddirection by the other three-dimensional head and the second head whenthe moving member moves in the first predetermined range.
 59. Theexposure apparatus according to claim 57 wherein the driving systemupdates grid errors in the third direction at each position in thesecond direction of the coordinate system of the first measurementsystem, based on measurement information in the third direction by thefirst head and the second head when the moving member moves in the firstpredetermined range.
 60. The exposure apparatus according to claim 57wherein the driving system updates grid errors in the second directionat each position in the first direction of the coordinate system of thefirst measurement system, based on measurement information in the seconddirection by the other three-dimensional head and the second head whenthe moving member moves in the first predetermined range.
 61. Theexposure apparatus according to claim 56 wherein the driving systemupdates grid errors in the first direction at each position in the firstdirection of the coordinate system of the first measurement system,based on measurement information in the first direction by the one ofthe three-dimensional heads and the first head when the moving membermoves in the first predetermined range.
 62. The exposure apparatusaccording to claim 56 wherein the driving system updates grid errors inthe third direction at each position in the first direction of thecoordinate system of the first measurement system, based on measurementinformation in the third direction by the one of the three-dimensionalheads and the first head when the moving member moves in the firstpredetermined range.
 63. The exposure apparatus according to claim 53wherein the driving system updates grid errors in the second directionat each position in the second direction of the coordinate system of thefirst measurement system, based on measurement information in the seconddirection by the pair of three-dimensional heads when the moving membermoves in the first predetermined range.
 64. The exposure apparatusaccording to claim 53 wherein the driving system updates grid errors inthe first direction at each position in the second direction of thecoordinate system of the first measurement system, based on measurementinformation in the first direction by the pair of three-dimensionalheads when the moving member moves in the first predetermined range. 65.The exposure apparatus according to claim 48 wherein the firstmeasurement system measures position information of the moving member inmore than six degrees of freedom, based on measurement information bythe plurality of heads, whereby the driving system updates grid errorsin the predetermined measurement direction of a coordinate system of thefirst measurement system when the moving member moves in the firstpredetermined range, based on a difference between position informationof the moving member in a predetermined measurement direction which is apart of position information used to drive the moving member in sixdegrees of freedom and redundant position information which is differentfrom such position information and is not used when driving the movingmember in six degrees of freedom in the predetermined measurementdirection.
 66. The exposure apparatus according to claim 1 wherein thedriving system calculates backward and updates a grid distortion of acoordinate system of the second measurement system based on a grid of acoordinate system of the first measurement system, from a relationbetween partial coordinate systems that mutually correspond to thesecond measurement system and the first measurement system.
 67. Theexposure apparatus according to claim 1, the apparatus furthercomprising: a liquid immersion device which supplies liquid right belowthe optical system, wherein on exposure of the object, a liquidimmersion area is formed between the optical system and an object heldby the moving member by the liquid immersion device.
 68. The exposureapparatus according to claim 1 wherein the first grating consists of aplurality of parts.
 69. A device manufacturing method, comprising:exposing an object using the exposure apparatus according to claim 1;and developing the object which has been exposed.
 70. An exposureapparatus which exposes a substrate via an optical system, the apparatuscomprising: a frame member which supports the optical system; asubstrate stage which has a mounting area of the substrate and a firstgrating member placed lower than the mounting area; a driving systemwhich drives the substrate stage; a first measurement system which has ahead section placed lower than the first grating member, and measuresposition information of the substrate stage by irradiating a firstmeasurement beam from below to the first grating member, via the headsection facing the first grating by the substrate stage being positionedfacing the optical system; a second measurement system which has aplurality of heads provided on one of the frame member and the substratestage, and measures position information of the substrate stage byirradiating each of a second measurement beam via the plurality of headson a second grating member provided on the other of the frame member andthe substrate stage; and a controller which controls a drive of thesubstrate stage by the driving system, based on position informationmeasured by at least one of the second measurement systems.
 71. Theexposure apparatus according to claim 70, the apparatus furthercomprising: a support member which is connected to the frame member, andsupports the head section so that the head section is placed lower thanthe first grating member, wherein the controller uses positioninformation measured by at least the second measurement system for drivecontrol of the substrate stage, in at least a part of a frequency bandof vibration where measurement reliability of the first measurementsystem becomes lower than measurement reliability of the secondmeasurement system due to vibration of the head section.
 72. Theexposure apparatus according to claim 70 wherein the first measurementsystem irradiates a plurality of the first measurement beams on thefirst grating member so as to measure position information in directionsof six degrees of freedom of the substrate stage, and also irradiates atleast one first measurement beam different from the plurality of thefirst measurement beams, and the controller updates information whichcompensates measurement errors of the first measurement system occurringdue to the first grating member, using position information of thesubstrate stage measured with the first measurement system by the atleast one first measurement beam different from the plurality of thefirst measurement beams.
 73. A device manufacturing method, comprising:exposing an object using the exposure apparatus according to claim 70;and developing the object which has been exposed.
 74. An exposure methodin which an object is exposed by an energy beam via an optical system,the method comprising: measuring position information of a moving memberon which the object is mounted and is movable while holding the objectalong a predetermined plane including a first axis and a second axisorthogonal to each other, in degrees of freedom of more than threeincluding three degrees of freedom within the predetermined plane whenthe moving member moves within a first predetermined range within anexposure station where the object is exposed by the energy beam, basedon measurement information according to a first measurement system whichincludes a plurality of heads that each measures position information ofthe moving member in at least one measurement direction, with themeasurement direction being a first direction parallel to the firstaxis, a second direction parallel to the second axis, and a thirddirection orthogonal to the predetermined plane, by each headirradiating each of a first measurement beam on a grating provided on arear surface side of a mounting surface on which the object is mountedof the moving member and receiving each return light from the grating,and updating grid errors in a predetermined measurement direction of acoordinate system of the first measurement system, based on a differencebetween position information of the moving member in the predeterminedmeasurement direction which is a part of position information used todrive the moving member in a first predetermined number of degrees offreedom of three or more including three degrees of freedom within thepredetermined plane and redundant position information of the movingmember in the predetermined measurement direction which is not used whendriving the moving member in the first predetermined number of degreesof freedom, while driving the moving member within the firstpredetermined range and controlling a position of the moving member indirections of the first predetermined number of degrees of freedom basedon the measurement information by the plurality of heads.
 75. Theexposure method according to claim 74 wherein the first grating is atwo-dimensional grating having a predetermined area, placed on the rearsurface of the mounting surface of the moving member.
 76. The exposuremethod according to claim 74 wherein the moving member structures a partof a movable body which has a space inside and moves at least along thepredetermined plane.
 77. The exposure method according to claim 76wherein the movable body includes a movable member which has a spaceinside and can move at least along the predetermined plane, and themoving member which is movably supported by the movable member at leastwithin a plane parallel to the predetermined plane.
 78. The exposuremethod according to claim 76 wherein in the measuring, measurement ofthe position information is performed using a first measurement arm thathas an arm member which is supported in a cantilevered state and can beinserted into the space from one side of the first direction, and theplurality of heads which have at least a part of each of the headsprovided on a surface of the arm member that can face the grating. 79.The exposure method according to claim 78 wherein the arm member has anunequal sectional shape whose fixed end is larger than a free end. 80.The exposure method according to claim 78 wherein the arm member ishollow.
 81. The exposure method according to claim 78 wherein the armmember is made of a low thermal expansion material.
 82. The exposuremethod according to claim 78 wherein a damping member is attached to thefree end of the arm member.
 83. The exposure method according to claim78 wherein the first predetermined number of degrees of freedom is sixdegrees of freedom.
 84. The exposure method according to claim 83wherein the plurality of heads include a pair of three-dimensional headswhich measures position information of the moving member in the firstdirection, the second direction, and the third direction, with twopoints which are positioned at the same position in the first directionand whose positions are different in the second direction serving aseach measurement point.
 85. The exposure method according to claim 84wherein a point directly below an irradiation position of the energybeam serves as the measurement point of one of the pair ofthree-dimensional heads.
 86. The exposure method according to claim 84wherein two points symmetrical in the second direction with respect toan irradiation position of the energy beam serve as the measurementpoint of each of the pair of three-dimensional heads.
 87. The exposuremethod according to claim 84 wherein the plurality of heads furtherinclude a first head whose measurement point is a point which is on astraight line in the first direction passing through a measurement pointof one of the pair of three-dimensional heads and is located apredetermined distance away from the measurement point of one of thepair of three-dimensional heads, with one third directions serving asmeasurement directions.
 88. The exposure method according to claim 87wherein the plurality of heads further include a second head whosemeasurement point is an intersecting point of a straight line in thefirst direction passing through the measurement point of the other ofthe pair of three-dimensional heads and a straight line in the seconddirection passing through the measurement point of the first head, withthe second and third directions serving as measurement directions. 89.The exposure method according to claim 88 wherein in the updating griderrors, grid errors in the second direction at each position in thefirst direction of the coordinate system of the first measurement systemis updated, based on measurement information in the second direction bythe other three-dimensional head and the second head when the movingmember moves in the first predetermined range.
 90. The exposure methodaccording to claim 88 wherein in the updating grid errors, grid errorsin the third direction at each position in the second direction of thecoordinate system of the first measurement system is updated, based onmeasurement information in the third direction by the first head and thesecond head when the moving member moves in the first predeterminedrange.
 91. The exposure method according to claim 88 wherein in theupdating grid errors, grid errors in the second direction at eachposition in the first direction of the coordinate system of the firstmeasurement system is updated, based on measurement information in thesecond direction by the other of the three-dimensional heads and thesecond head when the moving member moves in the first predeterminedrange.
 92. The exposure method according to claim 87 wherein in theupdating grid errors, grid errors in the first direction at eachposition in the first direction of the coordinate system of the firstmeasurement system is updated, based on measurement information in thefirst direction by one of the three-dimensional heads and the first headwhen the moving member moves in the first predetermined range.
 93. Theexposure method according to claim 87 wherein in the updating griderrors, grid errors in the third direction at each position in the firstdirection of the coordinate system of the first measurement system isupdated, based on measurement information in the third direction by oneof the three-dimensional heads and the first head when the moving membermoves in the first predetermined range.
 94. The exposure methodaccording to claim 84 wherein in the updating grid errors, grid errorsin the second direction at each position in the second direction of thecoordinate system of the first measurement system is updated, based onmeasurement information in the second direction by the pair ofthree-dimensional heads when the moving member moves in the firstpredetermined range.
 95. The exposure method according to claim 84wherein in the updating grid errors, grid errors in the first directionat each position in the second direction of the coordinate system of thefirst measurement system is updated, based on measurement information inthe first direction by the pair of three-dimensional heads when themoving member moves in the first predetermined range.
 96. The exposuremethod according to claim 78, the method further comprising: driving themoving member in a second predetermined range different from the firstpredetermined range within the predetermined plane, while controlling aposition of the moving member in directions of a second predeterminednumber of degrees of freedom of three or more including three degrees offreedom within the predetermined plane, based on measurement informationby a second measurement system which includes a plurality of heads thateach measure position information of the moving member in at least onemeasurement direction, with the measurement direction being the firstdirection, the second direction, and the third direction, by eachirradiating a second measurement beam on the grating and by eachreceiving a return light from the grating.
 97. The exposure methodaccording to claim 96 wherein in driving the moving member in a secondpredetermined range, further, grid errors in a predetermined measurementdirection of the coordinate system of the second measurement system isupdated, based on a difference between position information of themoving member in the predetermined measurement direction which is a partof position information used to drive the moving member in the secondpredetermined number of degrees of freedom, and redundant positioninformation of the moving member in the predetermined measurementdirection which is not used when driving the moving member in the secondpredetermined number of degrees of freedom.
 98. The exposure methodaccording to claim 96 wherein measurement of the position information bythe second measurement system is performed, using a second measurementarm which has an arm member which is in a cantilevered support stateinsertable from the other side of the first direction into the space,and the plurality of heads having at least a part of each head providedon a surface of the arm member that can face the grating.
 99. Theexposure method according to claim 98 wherein the arm member of thesecond measurement arm has an unequal sectional shape whose fixed end islarger than a free end.
 100. The exposure method according to claim 98wherein the arm member of the second measurement arm is hollow.
 101. Theexposure method according to claim 98 wherein the arm member of thesecond measurement arm is made of a low thermal expansion material. 102.The exposure method according to claim 98 wherein a damping member isattached to the free end of the arm member of the second measurementarm.
 103. The exposure method according to claim 98 wherein the secondpredetermined number of degrees of freedom is six degrees of freedom.104. The exposure method according to claim 103 wherein the plurality ofheads of the second measurement system include a pair ofthree-dimensional heads which measures position information of themoving member in the first direction, the second direction, and thethird direction, with two points which are positioned at the sameposition in the first direction and whose positions are different in thesecond direction serving as each measurement point.
 105. The exposuremethod according to claim 104 wherein a mark detection system is furtherprovided whose detection center is placed on the other side of the firstdirection from an exposure position where the energy beam is irradiatedon the object, and detects a mark provided on the object, and ameasurement point of one of the pair of three-dimensional heads of thesecond measurement system coincides with the detection center of themark detection system.
 106. The exposure method according to claim 104wherein two points symmetric in the second direction with respect to thedetection center of the mark detection system serve as measurementpoints of each of the pair of three-dimensional heads.
 107. The exposuremethod according to claim 105 wherein the second predetermined range isa range within a measurement station where detection of a mark on theobject is performed by the mark detection system.
 108. The exposuremethod according to claim 104 wherein the plurality of heads of thesecond measurement system further include a first two-dimensional headwhose measurement point is a point which is a predetermined distanceaway from the measurement point on a straight line in the firstdirection passing through one of the measurement points of the pair ofthree-dimensional heads, with the first direction and the thirddirection serving as measurement directions.
 109. The exposure methodaccording to claim 108 wherein the plurality of heads of the secondmeasurement system further include a second two-dimensional head whosemeasurement point is an intersecting point of a straight line in thefirst direction passing through a measurement point of the otherthree-dimensional head of the pair of three-dimensional heads and astraight line in the second direction passing through a measurementpoint of the first two-dimensional head, with the second and the thirddirections serving as measurement directions.
 110. The exposure methodaccording to claim 103 wherein a surface position detection system isfurther provided which detects surface position information of theobject in the third direction serving as an optical axis direction ofthe optical system, and the plurality of heads of the second measurementsystem further include a pair of two-dimensional heads which measureposition information of the moving member in the second and the thirddirections, with two points on a straight line in the second directionpassing through the detection center of the surface position detectionsystem serving as each measurement point.
 111. The exposure methodaccording to claim 78 wherein another moving member is further providedin which at least a part of the member can face the first measurementarm and a two-dimensional grating is provided on its facing section, andis movable independent from the moving member along the predeterminedplane.
 112. The exposure method according to claim 111 wherein theanother moving member has a sectional shape engageable to the firstmeasurement arm from a direction intersecting the first direction. 113.The exposure method according to claim 111 wherein the another movingmember has a measurement member.
 114. The exposure method according toclaim 74 wherein exposure of the object is performed in a state where aliquid immersion area is formed between the optical system and an objectheld by the moving member.
 115. The exposure method according to claim74 wherein the grating consists of a plurality of parts.
 116. A devicemanufacturing method, comprising: exposing an object using the exposuremethod according to claim 74; and developing the object which has beenexposed.
 117. An exposure apparatus which exposes an object via anoptical system by an energy beam, the apparatus comprising: a movingmember holding the object which is movable along a predetermined planeincluding a first axis and a second axis that are orthogonal to eachother while having a grating at a position on an opposite side of theoptical system provided with respect to a mounting surface on which theobject is mounted; a first measurement system which has a plurality ofheads measuring position information of the moving member in at leastone measurement direction, with the measurement direction being a firstdirection parallel to the first axis, a second direction parallel to thesecond axis, and a third direction orthogonal to the predeterminedplane, by each of the plurality of heads irradiating each of a firstmeasurement beam on the grating and receiving return lights from thegrating, and measures position information of the moving member in themeasurement direction in degrees of freedom of more than three includingthree degrees of freedom within the predetermined plane based onmeasurement information according to the plurality of heads when themoving member moves within a first predetermined range within anexposure station where the object is exposed by the energy beam; and adriving system which drives the moving member while controlling aposition of the moving member in directions of a first predeterminednumber of degrees of freedom of three or more including three degrees offreedom within the predetermined plane based on measurement informationby the plurality of heads when the moving member moves in the firstpredetermined range, and updates grid errors in a predeterminedmeasurement direction of a coordinate system of the first measurementsystem, based on a difference between position information of the movingmember in the predetermined measurement direction which is a part ofposition information used to drive the moving member in the firstpredetermined number of degrees of freedom and redundant positioninformation of the moving member in the predetermined measurementdirection which is not used when driving the moving member in the firstpredetermined number of degrees of freedom.
 118. The exposure apparatusaccording to claim 117 wherein the grating is a two-dimensional gratingof a predetermined area placed on a surface on an opposite side of themounting surface of the moving member.
 119. The exposure apparatusaccording to claim 117 wherein the moving member structures a part of amovable body which has a space inside and moves at least along thepredetermined plane.
 120. The exposure apparatus according to claim 119wherein the movable body includes a movable member which has a spaceinside and can move at least along the predetermined plane, and themoving member which is movably supported by the movable member at leastwithin a plane parallel to the predetermined plane.
 121. The exposureapparatus according to claim 119 wherein the first measurement systemincludes a first measurement arm that has an arm member which issupported in a cantilevered state and can be inserted into the spacefrom one side of the first direction, and the plurality of heads whichhave at least a part of each of the heads provided on a surface of thearm member that can face the grating.
 122. The exposure apparatusaccording to claim 121 wherein the arm member has an unequal sectionalshape whose fixed end is larger than a free end.
 123. The exposureapparatus according to claim 121 wherein the arm member is hollow. 124.The exposure apparatus according to claim 121 wherein the arm member ismade of a low thermal expansion material.
 125. The exposure apparatusaccording to claim 121 wherein a damping member is attached to the freeend of the arm member.
 126. The exposure apparatus according to claim121 wherein the first predetermined number of degrees of freedom is sixdegrees of freedom.
 127. The exposure apparatus according to claim 126wherein the plurality of heads include a pair of three-dimensional headswhich are measure position information of the moving member in the firstdirection, the second direction, and the third direction, with twopoints which are positioned at the same position in the first directionand whose positions are different in the second direction serving aseach measurement point.
 128. The exposure apparatus according to claim127 wherein a point directly below an irradiation position of the energybeam serves as the measurement point of one of the pair ofthree-dimensional heads.
 129. The exposure apparatus according to claim127 wherein two points symmetrical in the second direction with respectto an irradiation position of the energy beam serve as the measurementpoint of each of the pair of three-dimensional heads.
 130. The exposureapparatus according to claim 127 wherein the plurality of heads furtherinclude a first head whose measurement point is a point which is on astraight line in the first direction passing through a measurement pointof one of the pair of three-dimensional heads and is located apredetermined distance away from the measurement point of one of thepair of three-dimensional heads, with one third directions serving asmeasurement directions.
 131. The exposure apparatus according to claim130 wherein the plurality of heads further include a second head whosemeasurement point is an intersecting point of a straight line in thefirst direction passing through the measurement point of the other ofthe pair of three-dimensional heads and a straight line in the seconddirection passing through the measurement point of the first head, withthe second and third directions serving as measurement directions. 132.The exposure apparatus according to claim 131 wherein the driving systemupdates grid errors in the second direction at each position in thefirst direction of the coordinate system of the first measurementsystem, based on measurement information in the second direction by theother three-dimensional head and the second head when the moving membermoves in the first predetermined range.
 133. The exposure apparatusaccording to claim 131 wherein the driving system updates grid errors inthe third direction at each position in the second direction of thecoordinate system of the first measurement system, based on measurementinformation in the third direction by the first head and the second headwhen the moving member moves in the first predetermined range.
 134. Theexposure apparatus according to claim 131 wherein the driving systemupdates grid errors in the second direction at each position in thefirst direction of the coordinate system of the first measurementsystem, based on measurement information in the second direction by theother three-dimensional head and the second head when the moving membermoves in the first predetermined range.
 135. The exposure apparatusaccording to claim 130 wherein the driving system updates grid errors inthe first direction at each position in the first direction of thecoordinate system of the first measurement system, based on measurementinformation in the first direction by the one of the three-dimensionalheads and the first head when the moving member moves in the firstpredetermined range.
 136. The exposure apparatus according to claim 130wherein the driving system updates grid errors in the third direction ateach position in the first direction of the coordinate system of thefirst measurement system, based on measurement information in the thirddirection by the one of the three-dimensional heads and the first headwhen the moving member moves in the first predetermined range.
 137. Theexposure apparatus according to claim 127 wherein the driving systemupdates grid errors in the second direction at each position in thesecond direction of the coordinate system of the first measurementsystem, based on measurement information in the second direction by thepair of three-dimensional heads when the moving member moves in thefirst predetermined range.
 138. The exposure apparatus according toclaim 127 wherein the driving system updates grid errors in the firstdirection at each position in the second direction of the coordinatesystem of the first measurement system, based on measurement informationin the first direction by the pair of three-dimensional heads when themoving member moves in the first predetermined range.
 139. The exposureapparatus according to claim 121, the apparatus further comprising: asecond measurement system which has a plurality of heads that eachmeasure position information of the moving member in at least onemeasurement direction, with the measurement direction being the firstdirection, the second direction, and the third direction, by eachirradiating each of a second measurement beam on the grating and eachreceiving a return light from the grating, and based on measurementinformation by the plurality of heads, measures position information ofthe moving member in degrees of freedom of more than three includingthree degrees of freedom within the predetermined plane when the movingmember moves in a second predetermined range-different from the firstpredetermined range within the predetermined plane, wherein the drivingsystem drives the moving member, while controlling a position of themoving member in directions of a second predetermined number of degreesof freedom of three or more including three degrees of freedom withinthe predetermined plane, based on measurement information by theplurality of heads when the moving member moves in the secondpredetermined range.
 140. The exposure apparatus according to claim 139wherein the driving system updates grid errors in a predeterminedmeasurement direction of the coordinate system of the second measurementsystem when the moving member is driven in the second predeterminedrange, based on a difference between position information of the movingmember in the predetermined measurement direction which is a part ofposition information used to drive the moving member in the secondpredetermined number of degrees of freedom and redundant positioninformation of the moving member in the predetermined measurementdirection which is not used when driving the moving member in the secondpredetermined number of degrees of freedom.
 141. The exposure apparatusaccording to claim 139 wherein the second measurement system includes asecond measurement arm that has an arm member which is supported in acantilevered state and can be inserted into the space from the otherside of the first direction, and the plurality of heads which have atleast a part of each of the heads provided on a surface of the armmember that can face the grating.
 142. The exposure apparatus accordingto claim 141 wherein the arm member of the second measurement arm has anunequal sectional shape whose fixed end is larger than a free end. 143.The exposure apparatus according to claim 141 wherein the arm member ofthe second measurement arm is hollow.
 144. The exposure apparatusaccording to claim 141 wherein the arm member of the second measurementarm is made of a low thermal expansion material.
 145. The exposureapparatus according to claim 141 wherein a damping member is attached tothe free end of the arm member of the second measurement arm.
 146. Theexposure apparatus according to claim 141 wherein the secondpredetermined number of degrees of freedom is six degrees of freedom.147. The exposure apparatus according to claim 146 wherein the pluralityof heads of the second measurement system include a pair ofthree-dimensional heads which measures position information of themoving member in the first direction, the second direction, and thethird direction, with two points which are positioned at the sameposition in the first direction and whose positions are different in thesecond direction serving as each measurement point.
 148. The exposureapparatus according to claim 147, the apparatus further comprising: amark detection system which detects a mark provided on the object whosedetection center is placed on one side of the first direction from anexposure position where the energy beam is irradiated on the object,wherein a measurement point of one of the pair of three-dimensionalheads of the second measurement system coincides with the detectioncenter of the mark detection system.
 149. The exposure apparatusaccording to claim 147 wherein two points symmetric in the seconddirection with respect to the detection center of the mark detectionsystem serve as measurement points of the pair of three-dimensionalheads, respectively.
 150. The exposure apparatus according to claim 148wherein the second predetermined range is a range of a measurementstation in which detection of a mark on the object by the mark detectionsystem is performed.
 151. The exposure apparatus according to claim 147wherein the plurality of heads of the second measurement system furtherincludes a first two-dimensional head whose measurement point is a pointwhich is on a straight line in the first direction passing through ameasurement point of one of the pair of three-dimensional heads and islocated a predetermined distance away from the measurement point of oneof the pair of three-dimensional heads, with the first direction and thethird direction serving as measurement directions.
 152. The exposureapparatus according to claim 135 wherein the plurality of heads of thesecond measurement system further includes a second two-dimensional headwhose measurement point is an intersecting point of a straight line inthe first direction passing through the measurement point of the otherof the pair of three-dimensional heads and a straight line in the seconddirection passing through the measurement point of the firsttwo-dimensional head, with the second and third directions serving asmeasurement directions.
 153. The exposure apparatus according to claim146, the apparatus further comprising: a surface position detectionsystem which detects surface position information of the object in thethird direction serving as an optical axis direction of the opticalsystem, wherein the plurality of heads of the second measurement systemfurther include a pair of two-dimensional heads which measure positioninformation of the moving member in the second and third directions,with two points on a straight-line in the second direction passingthrough the detection center of the surface position detection systemserving as each measurement point.
 154. The exposure apparatus accordingto claim 121, the apparatus further comprising: another moving member inwhich at least a part of the member can face the first measurement armand a two-dimensional grating is provided on its facing section, and ismovable independent from the moving member along the predeterminedplane.
 155. The exposure apparatus according to claim 154 wherein theanother moving member has a sectional shape engageable to the firstmeasurement arm from a direction intersecting the first direction. 156.The exposure apparatus according to claim 154 wherein the another movingmember has a measurement member.
 157. The exposure apparatus accordingto claim 117, the apparatus further comprising: a liquid immersiondevice which supplies liquid to a space right below the optical system,wherein on exposure of the object, a liquid immersion area is formedbetween the optical system and an object held by the moving member bythe liquid immersion device.
 158. The exposure apparatus according toclaim 117 wherein the grating consists of a plurality of parts.
 159. Adevice manufacturing method, comprising: exposing an object using theexposure apparatus according to claim 117; and developing the objectwhich has been exposed.
 160. An exposure method in which a substrate isexposed via an optical system, the method comprising: positioning asubstrate stage having a mounting area of the substrate and a firstgrating member placed lower than the mounting area so that the substratestage faces the optical system; measuring position information of thesubstrate stage by a first measurement system which irradiates a firstmeasurement beam from below on the first grating member, via a headsection facing the first grating member of the substrate stagepositioned to face the optical system; measuring position information ofthe substrate stage by a second measurement system which irradiates asecond measurement beam, via each of a plurality of heads provided inone of a frame member supporting the optical system and the substratestage, on a second grating member provided in the other of the framemember and the substrate stage; and controlling a drive of the substratestage by a driving system, based on position information measured by atleast one of the first measurement system and the second measurementsystem.
 161. The exposure method according to claim 160 wherein the headsection is supported by a support member connected to the frame memberso that the head section is placed lower than the first grating member,whereby in at least a part of a frequency band of vibration of the headsection in which measurement reliability of the first measurement systembecomes lower than measurement reliability of the second measurementsystem by the vibration, position information measured at least by thesecond measurement system is used for drive control of the substratestage.
 162. The exposure method according to claim 160 wherein at leastone first measurement beam different from a plurality of the firstmeasurement beams irradiated on the first grating member to measureposition information in direction of six degrees of freedom of thesubstrate stage by the first measurement system is irradiated on thefirst grating member, whereby information which compensates measurementerrors of the first measurement system occurring due to the firstgrating member is updated, using position information of the substratestage measured with the first measurement system by the at least onefirst measurement beam different from the plurality of the firstmeasurement beams.
 163. A device manufacturing method, comprising:exposing a substrate using the exposure method according to claim 160;and developing the object which has been exposed.
 164. A making methodof an exposure apparatus which exposes a substrate via an opticalsystem, the method comprising: supporting the optical system with aframe member; placing a substrate stage having a mounting area of thesubstrate and a first grating member below the optical system supportedby the frame member; providing a driving system which drives thesubstrate stage; providing a first measurement system which has a headsection placed lower than the first grating member, and measuresposition information of the substrate stage by irradiating a firstmeasurement beam from below on the first grating member via the headsection which faces the first grating member by the substrate stagebeing positioned to face the optical system; providing a secondmeasurement system which has a plurality of heads provided in one of theframe member and the substrate stage, and measures position informationof the substrate stage by irradiating a second measurement beam via eachof the plurality of heads, on a second grating member provided in theother of the frame member and the substrate stage; and providing acontroller which controls a drive of the substrate stage by the drivingsystem, based on position information measured by at least one of thefirst measurement system and the second measurement system.